Make web UI able to filter for alert groups from just my teams

[deepy]

What would you like to see!

When viewing Alert groups in the UI I'd like a simple way to filter it to only include the teams that I'm part of

Product Area

Other

Anything else to add?

As an administrator the list of teams can get pretty big, and while I can manually pick each and every team I'm part of being able to filter to just the ones I'm part of would simplify this and avoid stale bookmarks

[github-actions]

The current version of Grafana OnCall, at the time this issue was opened, is v1.9.25. If your issue pertains to an older version of Grafana OnCall, please be sure to list it in the PR description. Thank you 😄!