refactor: replace zeebe and web-apps with camunda orchestration core

[aabouzaid]

Which problem does the PR fix?

Related to: #2525

What's in this PR?

Replace zeebe and web-apps with camunda orchestration core

Checklist

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BEGIN_COMMIT_OVERRIDE
refactor: replace zeebe and web-apps with camunda orchestration core

BREAKING CHANGE: Zeebe, Zeebe Gateway, Operate, and Tasklist have been replaced with Orchestration Core. Also, the Connectors configuration syntax was updated.

Regarding the release pipeline, the Alpha chart has also been added to the main workflow.
Release-As: 0.0.0-8.7.0-alpha2
END_COMMIT_OVERRIDE