CNDB 15032 SequentialWriter should open a write-only channel by default

[driftx]

What is the issue

SequentialWriter open a write-only channel by default

What does this PR fix and why was it fixed

Defaults SequentialWriter channels to write-only

[github-actions]

Checklist before you submit for review

• 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

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
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-1937 rejected by Butler

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1 regressions found
See build details here

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Found 1 new test failures

Test	Explanation	Runs	Upstream
o.a.c.io.util.PrefetchingRebuffererTest.testNonSequentialAccess (compression)	REGRESSION	🔴🔵	0 / 20

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Found 11 known test failures