Bump flask from 2.0.2 to 2.1.1

Bumps [flask](https://github.com/pallets/flask) from 2.0.2 to 2.1.1.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/main/CHANGES.rst)
- [Commits](pallets/flask@2.0.2...2.1.1)

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

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

Author: dependabot[bot]

requirements.txt

@@ -3,7 +3,7 @@ SQLAlchemy==1.4.32
 alembic==1.7.6
 Flask_Login==0.5.0
 Flask_Testing==0.8.1
-Flask==2.0.2
+Flask==2.1.1
 Werkzeug==2.0.2
 Flask_Migrate==3.1.0
 gunicorn==20.1.0