Allow compiled extensions to load extra Java sources from resources

[kevin-m-knight-gs]

Allow compiled extensions to load extra Java sources from resource files. Move the extra Java sources from core and relational extensions to resource files, and clean them up some. Also, clean up some related tests and execution end listeners.

[github-actions[bot]]

Test Results

   372 files     372 suites   1h 16m 20s :stopwatch: 3 493 tests 3 469 :heavy_check_mark: 24 :zzz: 0 :x: 4 589 runs  4 565 :heavy_check_mark: 24 :zzz: 0 :x:

Results for commit f3ffaa5c.

:recycle: This comment has been updated with latest results.