HCD-468: Increase the caching time of estimated partition count

[blambov]

What is the issue

HCD-468

Significant CPU pressure from interval tree construction during sstable set updates when the number of sstables is high.

What does this PR fix and why was it fixed

Increases the caching time of the estimated partition count metric, which can also cause CPU pressure in the presence of many single-partition sstables (usually from repair).

C* 5 already includes the interval tree improvements.

CC4 PR: #2552

[github-actions]

Checklist before you submit for review

• This PR adheres to the Definition of Done
• Make sure there is a PR and ticket 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%, check manually at SonarCloud page
• 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 IBM copyright header instead of the Apache License one (no DataStax copyright any longer)

[sonarqube-dx-prod]

Quality Gate passed

Issues
0 New issues
0 Fixed 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

[plpesvc-ds]

❌ Build ds-cassandra-pr-gate/PR-2571 rejected by Butler

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4 regressions found
See build details here

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Found 4 new test failures

Test	Explanation	Runs	Upstream
junit.framework.TestSuite.org.apache.cassandra.distributed.test.sai.features.FeaturesVersionSupportBATest-_jdk11	REGRESSION	🔴	0 / 30
o.a.c.concurrent.StageTimeMeasurementTest.executionAndQueueTimeAreCountedOnSubmitWithResult (compression)	REGRESSION	🔴	0 / 30
o.a.c.index.sai.cql.VectorCompaction100dTest.testOneToManyCompaction[version=eb enableNVQ=false] ()	NEW	🔴	0 / 30
o.a.c.index.sai.cql.VectorSiftSmallTest.testCompaction[ec false] ()	NEW	🔴	0 / 30

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No known test failures found