Tests running gradle are now split into 11 small sub-targets instead of running in one target on 15 shards.
This way tests are more efficient and it is easier to work with when you need to reproduce some flakiness
or fight test timeouts.

Group for the test is defined by package suffix, e.g.  `runsGradleBuild` or `runsGradleErrors`.

All targets are listed in runsGradleTargets.txt and runsIndexingWithGradleTargets.txt and can be executed all-together using:
bazel test --config=remote --nocache_test_results -- $(<project-system-gradle/runsGradleTargets.txt) $(<project-system-gradle/runsIndexingWithGradleTargets.txt)