Add Java 21 Compile Support

[Zeta201]

Purpose

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Goals

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Release note

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Documentation

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Training

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Certification

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Security checks

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• Ran FindSecurityBugs plugin and verified report? yes/no
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Samples

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Learning

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 70.73%. Comparing base (8b1519e) to head (a80b88c).
⚠️ Report is 6 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##             master      #25   +/-   ##
=========================================
  Coverage     70.73%   70.73%           
  Complexity        6        6           
=========================================
  Files             3        3           
  Lines            82       82           
  Branches          4        4           
=========================================
  Hits             58       58           
  Misses           22       22           
  Partials          2        2           

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[jenkins-is-staging]

PR builder started
Link: https://github.com/wso2/product-is/actions/runs/22192766109

[jenkins-is-staging]

PR builder completed
Link: https://github.com/wso2/product-is/actions/runs/22192766109
Status: failure

[jenkins-is-staging]

PR builder started
Link: https://github.com/wso2/product-is/actions/runs/22211324513

[jenkins-is-staging]

PR builder completed
Link: https://github.com/wso2/product-is/actions/runs/22211324513
Status: success

[jenkins-is-staging]

Approving the pull request based on the successful pr build https://github.com/wso2/product-is/actions/runs/22211324513