Bump flask from 2.0.2 to 2.3.2

Bumps [flask](https://github.com/pallets/flask) from 2.0.2 to 2.3.2.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/main/CHANGES.rst)
- [Commits](pallets/flask@2.0.2...2.3.2)

---
updated-dependencies:
- dependency-name: flask
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

requirements.txt

@@ -28,7 +28,7 @@ etebase==0.31.5
     # via etesync-dav (setup.py)
 etesync==0.12.1
     # via etesync-dav (setup.py)
-flask==2.0.2
+flask==2.3.2
     # via
     #   etesync-dav (setup.py)
     #   flask-wtf