A failed CI run is usually the first sign that something is broken, but acting on it still takes a person. Someone has to notice the red build, open the logs, and work out what changed before anything gets fixed.
Automations now trigger on five GitHub Actions events: workflow runs, workflow jobs, manual workflow dispatches, check runs and check suites. Scope any of them by organization, repository, branch or workflow name, and filter by conclusion or status, so an automation starts on the failures you care about and stays quiet for everything else. From there the automation picks up the failed run, works out why it broke, and can push a fix so the workflow runs again. See the documentation to set one up.