chore: Add labels to service

[armandgrillet]

What this PR does / why we need it:
This PR adds the possibility to set labels for the controller manager's services. This is useful as new Prometheus versions do not scrape services based on annotations anymore.

Special notes for your reviewer:

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[hectorj2f]

Thanks @armandgrillet

[hectorj2f]

/approve

[jimmidyson]

Please update chart readme then lgtm

[jimmidyson]

/lgtm
/approve

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: armandgrillet, hectorj2f, jimmidyson, makkes

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