CNDB-15670: Add Metric for DELETE Requests

[kathirsvn]

What is the issue

There are no metrics available to track the DELETE statements received from the clients

What does this PR fix and why was it fixed

A new per table metric called "DeleteRequests" is added.

• For every DELETE statement from the client, the new metric will be incremented
• For a batch of DELETEs, the metric will be incremented for each DELETE statement in the batch
• Even if more than one row is deleted by a DELETE statement, the delete requests metric will be incremented only once

[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

[driftx]

Left some comments around "if a DELETE statement delete multiple partition rows, the metric will be incremented only once" but I'm also not sure if that's the behavior we want. Maybe we do want to increment for each partition? I didn't find anything in the issue regarding this.

[driftx]

Looks good, don't forget to update the description.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-2223 rejected by Butler

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5 regressions found
See build details here

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Found 5 new test failures

Test	Explanation	Runs	Upstream
o.a.c.db.ColumnFamilyStoreTest.testDiscardSSTables	REGRESSION	🔴⚪	0 / 13
o.a.c.index.sai.cql.VectorCompaction100dTest.testPQRefine[ec false]	REGRESSION	🔴⚪	0 / 13
o.a.c.index.sai.cql.VectorCompaction2dTest.testZeroOrOneToManyCompaction[ca false] (compression)	REGRESSION	🔴🔴	0 / 13
o.a.c.index.sai.cql.VectorKeyRestrictedOnPartitionTest.partitionRestrictedTest[db false false] (compression)	REGRESSION	🔴🔵	0 / 13
o.a.c.index.sai.cql.VectorSiftSmallTest.testMultiSegmentBuild[ed false false]	REGRESSION	🔴⚪	0 / 13

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Found 3 known test failures