[Task]: Add Sentry to our healthchecks

[willdurand]

Description

Per https://docs.google.com/document/d/1k9TTukL_pOWG-gzO0lj8A3EGJFg2GDQEZEbqLiooC1A/edit?usp=sharing, we should monitor Sentry in our health checks somehow.

Acceptance Criteria

see above

┆Issue is synchronized with this Jira Task

[diox]

Ideally we could ping sentry - we don't want to report an entire traceback just for this.

[diox]

Worth double-checking and possibly filing a separate ticket for: during the network incident we had, were logs being reported in GCP correctly ? If so some alerting about those (since they include the severity) could be beneficial.

[diox]

Ideally we could ping sentry - we don't want to report an entire traceback just for this.

Actually in getsentry/sentry-python#1033 the suggestion was to do exactly that: generate an event that you can ignore in Sentry (it will get aggregated to the same issue in Sentry). You can then use the API to look that up, or just set up an alert in Sentry if there hasn't been any errors in some amount of time.

It would likely mess up Sentry metrics though...