sentry-related question prompted by an offhand note from jade in her GSoC pre-proposal on discourse...

although we have a project defined for (what looks like) mb-mail-service in sentry under the name "email" w/ platform set to rust, and the [docs for running mb-mail-service](https://github.com/metabrainz/mb-mail-service/blob/main/docs/OPERATING.md#sentry) allow for specification of a sentry DSN by env var, it doesn't look like that env var is actually *defined* anywhere the service containers are actually running. (started to suspect after seeing docker-server-configs/scripts/services.sh lines 2372-2382, confirmed by inspecting containers on selda and yamaoka) 

hence, sentry isn't getting any data from these mb-mail-service containers. is there a reason for this?