fix(livekit-server): add labels on servicemonitor

[genofire]

fix #97

[CLAassistant]

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[genofire]

i agree to the current license (apache) but no feature changes and i do not allow third-party to my github-account (here https://cla-assistant.io/ / SAP ) ...

[MartinWong06]

may I know got any update on this PR?