Bump flask from 3.1.2 to 3.1.3

Bumps [flask](https://github.com/pallets/flask) from 3.1.2 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@3.1.2...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]

src/requirements.txt

@@ -1,5 +1,5 @@
 # Core dependencies
-Flask[async]>=2.0.0
+Flask[async]>=3.1.3
 g4f>=0.2.0
 Werkzeug>=3.1.4