Bump uvicorn from 0.14.0 to 0.17.6

Bumps [uvicorn](https://github.com/encode/uvicorn) from 0.14.0 to 0.17.6.
- [Release notes](https://github.com/encode/uvicorn/releases)
- [Changelog](https://github.com/encode/uvicorn/blob/master/CHANGELOG.md)
- [Commits](encode/uvicorn@0.14.0...0.17.6)

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

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

requirements.txt

@@ -32,4 +32,4 @@ pytest-trio==0.7.0
 trio==0.19.0
 trio-typing==0.5.1
 trustme==0.9.0
-uvicorn==0.14.0
+uvicorn==0.17.6