Bump flask in /docs/examples/fork-process-model/flask-uwsgi

Bumps [flask](https://github.com/pallets/flask) from 1.1.2 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@1.1.2...2.3.2)

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

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

docs/examples/fork-process-model/flask-uwsgi/requirements.txt

@@ -1,5 +1,5 @@
 click==7.1.2
-Flask==1.1.2
+Flask==2.3.2
 googleapis-common-protos==1.52.0
 grpcio==1.35.0
 gunicorn==20.0.4