itest: separate tapd logs from itest

[darioAnongba]

Currently the logs of the tapd instance are mixed with the logs of the test suite on the console. This PR adds a logdir param used to set the logging directory of tapd in order to reduce the verbosity of the integration tests. It additionally removes unnecessary logging in the integration tests where we should verify actions by assertions.

[coveralls]

Pull Request Test Coverage Report for Build 18341956376

Details

• 0 of 8 (0.0%) changed or added relevant lines in 2 files are covered.
• 28024 unchanged lines in 197 files lost coverage.
• Overall coverage decreased (-21.9%) to 34.608%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
itest/tapd_harness.go	0	1	0.0%
itest/test_harness.go	0	7	0.0%

Files with Coverage Reduction	New Missed Lines	%
universe/supplyverifier/util.go	1	98.75%
proof/util.go	2	81.63%
tapdb/migrations.go	2	76.19%
tapdb/mssmt.go	2	88.64%
address/log.go	3	0.0%
commitment/log.go	3	0.0%
internal/pedersen/commitment.go	3	95.31%
lndservices/log.go	3	0.0%
rfq/log.go	3	0.0%
tapchannel/aux_leaf_signer.go	3	43.53%

Totals
Change from base Build 18323057272:	-21.9%
Covered Lines:	30524
Relevant Lines:	88200

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💛 - Coveralls