Bump uvicorn from 0.18.2 to 0.28.1

Bumps [uvicorn](https://github.com/encode/uvicorn) from 0.18.2 to 0.28.1.
- [Release notes](https://github.com/encode/uvicorn/releases)
- [Changelog](https://github.com/encode/uvicorn/blob/master/CHANGELOG.md)
- [Commits](encode/uvicorn@0.18.2...0.28.1)

---
updated-dependencies:
- dependency-name: uvicorn
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -1,5 +1,5 @@
 fastapi==0.78.0
-uvicorn==0.18.2
+uvicorn==0.28.1
 pydantic==1.9.1
 starlette-prometheus==0.9.0
 paramiko==2.11.0