fix(feedback): Check to verify that feedback has project, ts is a lie

[ryan953]

self-hosted users who recently upgraded noticed that some feedback items were not processed fully, and didn't have the expected project field in the response. This adds an extra check so we don't throw on that line of code.

Typescript in this case, is incorrect. It suggests that project is always present.

Self-hosted users, after the retention period, shouldn't need this line anymore... but we'll have to keep it in the codebase forever because folks can upgrade from an old to new version at anytime.

Fixes https://github.com/getsentry/sentry/issues/69258 Fixes https://github.com/getsentry/sentry/issues/70136