Jenkins migration 6.1

[cprovencher]

Action required after merging

pint merge them all the way up to master. Then you can close this PR.

Ticket

https://confluentinc.atlassian.net/browse/CPKAFKA-9986

Changes

1. Deletes the Jenkinsfile.
2. Adds the service-bot config (service.yml) and semaphore files generated by service-bot

Why are we migrating?

Read the background and motivation
Please merge this PR ASAP because we plan on shutting down Jenkins by the end of the year.

[cla-assistant]

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[cla-assistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}