Support usage of fastuuid

[kasium]

Problem Statement

I work in an application where performance in critical. We found out, that we can improve the speed by using fastuuid instead of the stdlibs uuid. Sentry doesn't allow use easily to change that, so a monkeypatch is needed

sentry_sdk.tracing.uuid = fastuuid
sentry_sdk.client.uuid = fastuuid

Solution Brainstorm

1. Allow users to specify the uuid module/function somehow
2. Support fastuuid natively in sentry