Bump websockets from 8.1 to 9.1

Bumps [websockets](https://github.com/aaugustin/websockets) from 8.1 to 9.1.
- [Release notes](https://github.com/aaugustin/websockets/releases)
- [Changelog](https://github.com/aaugustin/websockets/blob/9.1/docs/changelog.rst)
- [Commits](python-websockets/websockets@8.1...9.1)

---
updated-dependencies:
- dependency-name: websockets
  dependency-type: direct:production
...

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

requirements.txt

@@ -6,7 +6,7 @@ pydantic==1.7.2
 starlette==0.13.6
 uvicorn==0.12.3
 uvloop==0.17.0
-websockets==8.1
+websockets==9.1
 sentry-sdk==0.19.4
 python-dotenv==0.15.0
 sqlalchemy==1.3.20