web: `Team Labeler` Github action
Created by: valerybugakov
Description
@sourcegraph/frontend-platform uses a couple of Slack integrations based on the team label. It would be great if robots could add team labels for us based on the configuration file and PR owner. This PR introduces such Github action. It uses Team Labeler action. .github/teams.yml
was created based on Github teams in Sourcegraph org.
Tested here: https://github.com/sourcegraph/sourcegraph/pull/19742.