build(deps-dev): bump responses from 0.12.1 to 0.13.3 in /backend (#915)

Bumps [responses](https://github.com/getsentry/responses) from 0.12.1 to 0.13.3.
- [Release notes](https://github.com/getsentry/responses/releases)
- [Changelog](https://github.com/getsentry/responses/blob/master/CHANGES)
- [Commits](getsentry/responses@0.12.1...0.13.3)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

backend/requirements-dev.txt

@@ -2,4 +2,4 @@ fakeredis==1.5.0
 pre-commit==2.12.1
 pytest==6.2.2
 pytest-responses==0.5.0
-responses==0.12.1
+responses==0.13.3