Bump uvicorn from 0.11.5 to 0.11.7

Bumps [uvicorn](https://github.com/encode/uvicorn) from 0.11.5 to 0.11.7.
- [Release notes](https://github.com/encode/uvicorn/releases)
- [Changelog](https://github.com/encode/uvicorn/blob/master/CHANGELOG.md)
- [Commits](encode/uvicorn@0.11.5...0.11.7)

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

requirements.txt

@@ -11,6 +11,6 @@ numexpr==2.7.2
 numpy==1.14.0
 pydantic==1.5.1
 starlette==0.13.2
-uvicorn==0.11.5
+uvicorn==0.11.7
 websockets==8.1
 Werkzeug==1.0.1