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] <[email protected]>

Author: dependabot[bot]

requirements.txt

@@ -1,5 +1,5 @@
 uvicorn==0.12.1
-websockets==8.1
+websockets==9.1
 fastapi==0.65.2
 aioredis==1.3.1
 redis==3.5.3