Bump flask from 3.0.3 to 3.1.3 in /server

Bumps [flask](https://github.com/pallets/flask) from 3.0.3 to 3.1.3.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/main/CHANGES.rst)
- [Commits](pallets/flask@3.0.3...3.1.3)

---
updated-dependencies:
- dependency-name: flask
  dependency-version: 3.1.3
  dependency-type: direct:production
...

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

Author: dependabot[bot]

server/requirements.txt

@@ -2,7 +2,7 @@ astral==1.10.1
 cachetools==5.3.3
 croniter==2.0.5
 firebase-admin==6.5.0
-Flask==3.0.3
+Flask==3.1.3
 google-api-python-client==2.129.0
 google-cloud-vision==3.7.2
 numpy==1.26.4