CNDB-16516: Added Jenkinsfile for IBM TAAS

[maheshrajamani]

Added a Jenkinsfile that will used in cc Jenkins. Cloudbees Jenkins supported in UI scripting for multibranch but IBM TAAS needs it in the repository while using Pipeline: Multi branch plugin

What is the issue
Migrating the jenkins job from Cloudbees Jenkins to IBM TAAS. IBM TAAS is open source and does not support Cloudbees provided Multibranch plugin which allowed Jenkins job directly configured with custom script. To make the job work in IBM TAAS the job need to use OS Pipeline: Multibranch plugin which need the Jenkinsfile in the repo.

What does this PR fix and why was it fixed

Fixes CNDB-16516

[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

[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

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-2207 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.cql3.validation.operations.AggregationQueriesTest.testAggregationQueryShouldNotTimeoutWhenItExceedesReadTimeout (compression)	REGRESSION	🔴	0 / 19
o.a.c.distributed.test.jmx.JMXFeatureTest.testOneNetworkInterfaceProvisioning	REGRESSION	🔴	0 / 19
o.a.c.index.sai.cql.VectorCompaction100dTest.testZeroOrOneToManyCompaction[db true] ()	NEW	🔴	0 / 19

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Found 9 known test failures