Add custom annotations to Service Account

[sierrasoleil]

What this PR does / Why we need it: This PR adds the ability to include custom annotations on the Open Match service account. My specific use case is to allow that service account to leverage Workload Identity to write logs and metrics.

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[mridulji]

Hey @sierrasoleil, Could you please file an issue using applicable template to elaborate the problem faced and/or what solutions you suggest to it and mention that issue in this PR so that it will be helpful for community to understand it.

[mridulji]

@sierrasoleil, May I know if you are still working on it and would like to re-iterate that it would be very helpful if you file an issue explaining the problem.

[sierrasoleil]

@mridulji I submitted issue 1485 to explain the change.