Update dependency uwsgi to v2.0.20

Author: renovate-bot

requirements.txt

@@ -19,7 +19,7 @@ six==1.15.0; python_version >= "2.7" and python_full_version < "3.0.0" or python
 sortedcontainers==2.3.0; python_version >= "2.7" and python_full_version < "3.0.0" or python_full_version >= "3.5.0"
 sqlalchemy==1.3.20; python_version >= "2.7" and python_full_version < "3.0.0" or python_full_version >= "3.4.0"
 tenacity==6.2.0; python_version >= "2.7" and python_full_version < "3.0.0" or python_full_version >= "3.5.0"
-uwsgi==2.0.19.1
+uwsgi==2.0.20
 webassets==2.0
 werkzeug==1.0.1; python_version >= "2.7" and python_full_version < "3.0.0" or python_full_version >= "3.5.0"
 wtforms==2.3.3