Bump sentry-sdk from 0.8.0 to 0.9.0 (#241)

Bumps [sentry-sdk](https://github.com/getsentry/sentry-python) from 0.8.0 to 0.9.0.
- [Release notes](https://github.com/getsentry/sentry-python/releases)
- [Changelog](https://github.com/getsentry/sentry-python/blob/master/CHANGES.md)
- [Commits](getsentry/sentry-python@0.8.0...0.9.0)

Author: dependabot-preview[bot]

requirements.txt

@@ -4,4 +4,4 @@ gidgethub==3.1.0
 cachetools==3.1.1
 redis==3.2.1
 celery==4.3.0
-sentry-sdk==0.8.0
+sentry-sdk==0.9.0