What changes were proposed in this pull request?

flaky-test-check has problems running @Nested tests (e.g. TestLegacyReplicationManager).

Setting test class name:

• TestLegacyReplicationManager: no tests are run
• TestLegacyReplicationManager$Misreplicated: fails in prepare-job step, file is not found; also would require separate workflow run per nested class
• TestLegacyReplicationManager*: file found, tests executed OK (but twice), but artifact upload fails (artifact name includes test class name): The artifact name is not valid: ... Contains the following character: Asterisk *

Changes in this PR:

1. Remove the step that required the test class to be defined in a similarly named file.
   • junit.sh can execute tests in any module
   • misspelled test class results in failed run (implemented in HDDS-10080)
2. Avoid using test class in the artifact name. Instead it now includes the run id (e.g. 7743208137), which can be used to look up the run in Github. Since runs can be repeated, it also includes the run number (e.g. 187) to make it unique.
3. Add Abstract*$* to Surefire's test selector. In itself this will not cause any extra tests to execute, but it allows matching inherited @Nested tests.
4. Add set -x before running junit.sh to log the actual command.
5. (not required) Bump default number of splits to 10. Usually some multiple of 10x10 tests are run, because it helps define failure rate in percents.

https://issues.apache.org/jira/browse/HDDS-10264

How was this patch tested?

class = TestRootedOzoneContract, whose tests are defined as @Nested in the abstract parent class AbstractOzoneContractTest:
https://github.com/adoroszlai/ozone/actions/runs/7743208137

class = TestServiceInfoProvider$*, matches all nested tests in this concrete unit test:
https://github.com/adoroszlai/ozone/actions/runs/7743319908

class = TestMiniOzoneCluster, which is a regular integration test without any nested tests:
https://github.com/adoroszlai/ozone/actions/runs/7743334548

class = TestOMRatisSnapshots, method = testInstallIncrementalSnapshot, a specific method in a specific test class (without any nested tests):
https://github.com/adoroszlai/ozone/actions/runs/7743350631

class = TestServiceInfoProvider$UnsecureEnvironment: all methods in a nested test class:
https://github.com/adoroszlai/ozone/actions/runs/7743364840

class = TestLegacyReplicationManager$Misc, method = testGetContainerReplicaCount: specific method in a specific nested test class:
https://github.com/adoroszlai/ozone/actions/runs/7743385162