SOLR-17473: Introduce build tools formatting

[malliaridis]

https://issues.apache.org/jira/browse/SOLR-17473

Description

With the build tools persisting of various Java files, formatting and checking tools should also be run on these files.

Solution

This PR migrates the buildSrc to composite build project, as demonstrated in apache/lucene#13484 and applied in #2706 (with minor adjustments).

Tests

No tests have been added or altered.

Checklist

Please review the following and check all that apply:

• I have reviewed the guidelines for How to Contribute and my code conforms to the standards described there to the best of my ability.
• I have created a Jira issue and added the issue ID to my pull request title.
• I have given Solr maintainers access to contribute to my PR branch. (optional but recommended, not available for branches on forks living under an organisation)
• I have developed this patch against the main branch.
• I have run ./gradlew check.
• I have added tests for my changes.
• I have added documentation for the Reference Guide

[epugh]

I had no idea we had so many .java files related to doing our builds. I am always in favour of having more code strictness in an environment where many cooks are in the kitchen!

[epugh]

^ @malliaridis I triggered the github build and looks like something burped.

[dsmiley]

Since some of the build infra source files come from Lucene in their entirety, why not leave them be in the Lucene namespace? Lucene & Solr continue to have a build that's rather aligned, allowing taking of changes from one project to the other.

[malliaridis]

@dsmiley I thought the naming was just a legacy thing in this case, but for just this case I made a separate commit for the renaming, so that I can undo it easily.

@epugh thanks for executing the pipeline. The error seems not related to the changes though. Any idea what could be the cause?

[dsmiley]

I did another short look in a hurry. If I had more time, I might compare to Lucene project but I don't. +1 approval from me. I'll merge tomorrow but maybe sooner with someone else's +1.