Move auxiliary repos to span streaming/3.0 #8107

There are other packages used in Sentry that might not necessarily run alongside Sentry the monolith in the same environment, but they share the sentry-sdk version, for instance: taskbroker, pytest-sentry, devservices, …

If we move the sentry-sdk version in the monolith to 3.0, they'd stop working.

Make them forwards-compatible.