Publish action didn't call promote webhook

[LexManos]

Not sure why, will have to look into it later.

[Jonathing]

This is what GradleUtils 3.3 is meant to do. No more promoting through the webhook please, except for the super old stuff that can't use an updated Gradle yet.

Throw gradleutils.promote(it) in the publication, the same place where changelog.publish(it) goes.

[LexManos]

changelog.publish isn't in the current buildscript. But good to know i'll look into it later.