CPBR-2064: enabling cp jar build through service.yml

[rahejaprince]

This PR modifies service.yml to add cp jar build block in semaphore.yml to trigger cp jar build job on every PR build.

After merging the PR, cc-service-bot (which manages cp projects semaphore.yml) will be invoked on this repo to add cp-jar-build block in master branch.

Checklist

• Contains customer facing changes? Including API/behavior changes
• Is this change gated behind feature flag(s)?
  • List the LD flags needed to be set to enable this change
• Did you add sufficient unit test and/or integration test coverage for this PR?
  • If not, please explain why it is not required
• Does this change require modifying existing system tests or adding new system tests?
  • If so, include tracking information for the system test changes

References

JIRA:

Test & Review

Open questions / Follow-ups

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