[lang-test] Upgrade dokka maven plugin to 1.4.32

[adangel]

We currently need jcenter as a repository

pmd/pom.xml

Lines 931 to 943 in 1290999

	<pluginRepository>
	<!-- needed for dokka-maven-plugin in pmd-lang-test -->
	<id>jcenter</id>
	<name>JCenter</name>
	<releases>
	<enabled>true</enabled>
	<updatePolicy>never</updatePolicy>
	</releases>
	<snapshots>
	<enabled>false</enabled>
	</snapshots>
	<url>https://jcenter.bintray.com/</url>
	</pluginRepository>

But jcenter is basically obsolete, although they keep it running as read-only (so that e.g. our build doesn't break): https://jfrog.com/blog/into-the-sunset-bintray-jcenter-gocenter-and-chartcenter/ .
However, this created already a problem for reproducible builds (jvm-repo-rebuild/reproducible-central#70)

We currently use dokka 1.4.30.

It seems that upgrading to 1.4.32 is already sufficient, although this version still uses jcenter. At least I can build pmd with a fresh maven repo and without jcenter.

The new dokka version 1.6.10 only uses maven-central, but might require us to update kotlin etc.

[adangel]

Actually I wanted to update the kotlin version in this release... Should I do that early so that you can use the latest dokka 1.6.10?

I tested it with 1.4.32 and the update is unproblematic (see PR #3760). So there is no urgency required. The fix for the reproducible build is actually independent (it's just adding jcentral as a repo), but I wanted to take the chance to remove jcenter directly.

[oowekyala]

Ok great! I found out about your PR after writing my comment, which made no sense given there's already a PR. Thanks for looking into this, it sounds like a nice fix.