Update uvicorn to 0.51.0 (#6706)

Update uvicorn from 0.50.2 to 0.51.0

Author: pyup-bot

{{cookiecutter.project_slug}}/requirements/base.txt

@@ -16,7 +16,7 @@ flower==2.0.1  # https://github.com/mher/flower
 {%- endif %}
 {%- endif %}
 {%- if cookiecutter.use_async == 'y' %}
-uvicorn[standard]==0.50.2  # https://github.com/Kludex/uvicorn
+uvicorn[standard]==0.51.0  # https://github.com/Kludex/uvicorn
 uvicorn-worker==0.4.0  # https://github.com/Kludex/uvicorn-worker
 {%- endif %}