[fix](function) empty string should be cast to NULL(JSONB)

[mrhhsg]

What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[mrhhsg]

run buildall

[doris-robot]

TPC-H: Total hot run time: 40029 ms

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/tpch-tools
Tpch sf100 test result on commit b625cc86f14fa534e5d4a876e8df7188133375c6, data reload: false

------ Round 1 ----------------------------------
q1	17576	6906	6704	6704
q2	2060	203	164	164
q3	10579	1119	1099	1099
q4	10412	744	741	741
q5	7763	2881	2771	2771
q6	217	131	134	131
q7	948	631	606	606
q8	9581	1961	1958	1958
q9	8239	6380	6413	6380
q10	7001	2303	2343	2303
q11	458	253	260	253
q12	484	216	213	213
q13	17803	2964	3013	2964
q14	244	203	209	203
q15	510	463	459	459
q16	475	381	374	374
q17	966	627	556	556
q18	7125	6758	6741	6741
q19	1400	1083	1029	1029
q20	489	206	196	196
q21	3873	3195	3218	3195
q22	1084	992	989	989
Total cold run time: 109287 ms
Total hot run time: 40029 ms

----- Round 2, with runtime_filter_mode=off -----
q1	6681	6598	6599	6598
q2	332	234	229	229
q3	3012	2948	2944	2944
q4	2044	1901	1765	1765
q5	5742	5737	5713	5713
q6	211	132	136	132
q7	2190	1847	1815	1815
q8	3386	3546	3553	3546
q9	8837	8990	8846	8846
q10	3586	3517	3608	3517
q11	629	525	490	490
q12	830	631	676	631
q13	4785	3339	3318	3318
q14	325	294	288	288
q15	510	474	468	468
q16	530	456	463	456
q17	1869	1682	1623	1623
q18	8403	8231	7657	7657
q19	1692	1580	1509	1509
q20	2162	1948	1897	1897
q21	5341	4973	5065	4973
q22	1210	1046	1046	1046
Total cold run time: 64307 ms
Total hot run time: 59461 ms

[doris-robot]

TPC-DS: Total hot run time: 192268 ms

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/tpcds-tools
TPC-DS sf100 test result on commit b625cc86f14fa534e5d4a876e8df7188133375c6, data reload: false

query1	945	412	378	378
query2	6245	2001	1834	1834
query3	8682	200	193	193
query4	33786	23558	23306	23306
query5	3929	446	451	446
query6	282	196	188	188
query7	4207	318	324	318
query8	297	222	224	222
query9	9556	2591	2587	2587
query10	470	274	254	254
query11	17890	15250	15175	15175
query12	163	103	103	103
query13	1543	429	416	416
query14	9264	7358	6745	6745
query15	252	175	185	175
query16	8038	478	527	478
query17	1596	618	596	596
query18	2152	326	335	326
query19	375	163	161	161
query20	122	117	116	116
query21	211	106	110	106
query22	4779	4526	4521	4521
query23	35277	34192	34229	34192
query24	11176	2948	2938	2938
query25	685	431	415	415
query26	1462	180	189	180
query27	2807	354	367	354
query28	8019	2171	2179	2171
query29	976	500	443	443
query30	262	164	160	160
query31	1062	783	820	783
query32	103	54	53	53
query33	827	289	309	289
query34	1142	509	509	509
query35	855	743	738	738
query36	1113	965	959	959
query37	127	66	71	66
query38	4117	3989	3973	3973
query39	1510	1499	1504	1499
query40	264	100	100	100
query41	50	52	49	49
query42	124	104	98	98
query43	542	482	491	482
query44	1274	849	844	844
query45	190	169	176	169
query46	1159	748	729	729
query47	2012	1892	1945	1892
query48	479	394	400	394
query49	1079	421	404	404
query50	831	436	443	436
query51	7434	7188	7339	7188
query52	104	90	89	89
query53	263	188	183	183
query54	1455	483	472	472
query55	77	74	86	74
query56	266	249	245	245
query57	1322	1213	1202	1202
query58	222	213	207	207
query59	3300	3096	3031	3031
query60	285	258	250	250
query61	119	107	111	107
query62	895	670	686	670
query63	214	185	187	185
query64	4969	645	620	620
query65	3312	3226	3261	3226
query66	1403	293	300	293
query67	16069	15818	15623	15623
query68	4914	579	578	578
query69	449	266	262	262
query70	1206	1133	1137	1133
query71	354	257	284	257
query72	6180	4164	4070	4070
query73	768	347	356	347
query74	10583	9262	9012	9012
query75	3319	2648	2659	2648
query76	2904	1081	1105	1081
query77	384	268	269	268
query78	10602	9611	9550	9550
query79	2310	599	607	599
query80	1052	430	427	427
query81	535	225	220	220
query82	614	92	86	86
query83	238	146	145	145
query84	231	81	86	81
query85	1389	322	297	297
query86	444	306	298	298
query87	4401	4216	4320	4216
query88	4033	2384	2380	2380
query89	411	293	292	292
query90	2044	182	186	182
query91	193	154	151	151
query92	62	49	50	49
query93	2415	553	568	553
query94	942	295	285	285
query95	354	251	252	251
query96	627	292	285	285
query97	3277	3155	3171	3155
query98	213	205	193	193
query99	1510	1289	1323	1289
Total cold run time: 304975 ms
Total hot run time: 192268 ms

[doris-robot]

BE UT Coverage Report

Increment line coverage 66.67% (2/3) 🎉

Increment coverage report
Complete coverage report

Category	Coverage
Function Coverage	42.10% (11245/26712)
Line Coverage	32.62% (96266/295083)
Region Coverage	30.56% (55278/180897)
Branch Coverage	26.89% (27368/101788)

[doris-robot]

ClickBench: Total hot run time: 29.82 s

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/clickbench-tools
ClickBench test result on commit b625cc86f14fa534e5d4a876e8df7188133375c6, data reload: false

query1	0.03	0.04	0.03
query2	0.07	0.03	0.02
query3	0.23	0.07	0.06
query4	1.62	0.11	0.11
query5	0.53	0.52	0.51
query6	1.15	0.72	0.72
query7	0.02	0.02	0.02
query8	0.04	0.03	0.03
query9	0.58	0.50	0.50
query10	0.56	0.55	0.56
query11	0.14	0.10	0.11
query12	0.14	0.10	0.10
query13	0.62	0.60	0.59
query14	0.76	0.83	0.78
query15	0.85	0.84	0.82
query16	0.39	0.39	0.40
query17	0.99	1.03	0.98
query18	0.24	0.23	0.21
query19	1.83	1.87	1.85
query20	0.02	0.01	0.01
query21	15.44	0.60	0.57
query22	2.50	2.71	1.70
query23	17.18	0.97	0.79
query24	3.28	0.68	1.16
query25	0.16	0.29	0.10
query26	0.31	0.15	0.13
query27	0.03	0.04	0.03
query28	10.34	0.55	0.45
query29	12.58	3.20	3.20
query30	0.24	0.07	0.06
query31	2.85	0.38	0.38
query32	3.25	0.46	0.46
query33	3.01	3.05	3.03
query34	16.94	4.53	4.53
query35	4.59	4.57	4.61
query36	0.68	0.48	0.47
query37	0.08	0.05	0.06
query38	0.04	0.03	0.03
query39	0.03	0.02	0.03
query40	0.15	0.13	0.12
query41	0.08	0.02	0.02
query42	0.03	0.02	0.02
query43	0.04	0.03	0.03
Total cold run time: 104.64 s
Total hot run time: 29.82 s

[hello-stephen]

BE Regression && UT Coverage Report

Increment line coverage 100.00% (3/3) 🎉

Increment coverage report
Complete coverage report

Category	Coverage
Function Coverage	75.19% (19703/26205)
Line Coverage	68.49% (201208/293768)
Region Coverage	66.53% (120422/181001)
Branch Coverage	59.80% (61068/102112)