chore(deps): bump gunicorn in /tests/apps/python-flask

Bumps [gunicorn](https://github.com/benoitc/gunicorn) from 20.0.4 to 20.1.0.
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](https://github.com/benoitc/gunicorn/compare/20.0.4...20.1.0)

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

tests/apps/python-flask/requirements.txt

@@ -1,5 +1,5 @@
 Flask==1.1.2
 Jinja2==2.11.3
 Werkzeug==1.0.1
-gunicorn==20.0.4
+gunicorn==20.1.0