chore: update project config (#45)

### What this PR does?
更新项目配置

```release-note
None
```

Author: guqing

build.gradle

@@ -2,7 +2,7 @@ plugins {
     id 'java'
     id "com.github.node-gradle.node" version "7.0.2"
     id "io.freefair.lombok" version "8.0.1"
-    id "run.halo.plugin.devtools" version "0.1.1"
+    id "run.halo.plugin.devtools" version "0.2.0"
 }
 
 group 'run.halo.starter'
@@ -16,7 +16,7 @@ repositories {
 }
 
 dependencies {
-    implementation platform('run.halo.tools.platform:plugin:2.11.0-SNAPSHOT')
+    implementation platform('run.halo.tools.platform:plugin:2.20.0-SNAPSHOT')
     compileOnly 'run.halo.app:api'
 
     testImplementation 'run.halo.app:api'
@@ -52,5 +52,5 @@ build {
 }
 
 halo {
-    version = '2.17'
+    version = '2.20'
 }

src/main/resources/plugin.yaml

@@ -7,7 +7,7 @@ metadata:
   name: starter
 spec:
   enabled: true
-  requires: ">=2.11.0"
+  requires: ">=2.20.0"
   author:
     name: Halo
     website: https://github.com/halo-dev