#### What type of PR is this?
/kind feature
/area core
#### What this PR does / why we need it:
Use Gradle plugin `maven-publish` to publish Halo modules(`platform.application`, `platform.plugin` and `api`) to Maven central repository.
```bash
# Try to publish to Maven local repository.
./gradlew publish
# Really publish to Maven central repository.
./gradlew -Prelease publish -PossrhUsername=username -PossrhPassword=password
```
Note that currently we only support manually publishing.
#### Which issue(s) this PR fixes:
Fixes https://github.com/halo-dev/halo/issues/2730
#### Does this PR introduce a user-facing change?
```release-note
None
```
John Niang