CNDB-16069: Split VectorCompactionTest to prevent JUnit timeouts

[adelapena]

What is the issue

VectorCompaction100dTest and, to a lesser extent, VectorCompaction2dTest use to fail due to JUnit timeouts. These tests take too long to run, so probably we should split them.

What does this PR fix and why was it fixed

Split VectorCompaction100dTest and VectorCompaction2dTest into multiple tests.

[github-actions]

Checklist before you submit for review

• This PR adheres to the Definition of Done
• Make sure there is a PR in the CNDB project updating the Converged Cassandra version
• Use NoSpamLogger for log lines that may appear frequently in the logs
• Verify test results on Butler
• Test coverage for new/modified code is > 80%
• Proper code formatting
• Proper title for each commit staring with the project-issue number, like CNDB-1234
• Each commit has a meaningful description
• Each commit is not very long and contains related changes
• Renames, moves and reformatting are in distinct commits
• All new files should contain the DataStax copyright header instead of the Apache License one

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-2259 rejected by Butler

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3 regressions found
See build details here

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Found 3 new test failures

Test	Explanation	Runs	Upstream
o.a.c.index.sai.cql.VectorCompaction100dNVQTest.testZeroOrOneToManyCompaction[ca]	NEW	🔴⚪	0 / 21
o.a.c.index.sai.cql.VectorCompaction100dTest.testOneToManyCompaction[db]	NEW	🔴⚪	0 / 21
o.a.c.index.sai.cql.VectorSiftSmallTest.testMultiSegmentBuild[ec true false]	REGRESSION	🔴⚪	0 / 21

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Found 3 known test failures

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud