Add Github Action to test all affected modules

[HoustonPutman]

So I am really just testing around here. Now that we have a lot of functionality (and tests) split out into modules, it would be great if we could test the only the modules that are affected by a PR (Excluding solr-core for now).

This is pretty straightforward using the Dropbox Gradle plugin, but this does not work as well when running locally because the latest main commit might not actually be in the git history of the current branch (if it was forked from an earlier commit). This works well in github actions, however, because github will always merge the branch before running tests.

Still need to add docs here, and there are other issues that stem from this, such as core has a dependency on modules/analysis-extras, because of two tests. This means that if we change analysis-extras, it counts solr-core as an affected module, and thus wants to run the tests of every module except for SolrJ, since they depend on solr-core. If we move the ICUCollation field out of those tests and into analysis-extras tests, then this dependency won't exist anymore. Same for the recently created SQL Module, but that has a fix coming in the future anyways.

[github-actions[bot]]

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