Bump keras from 3.9.2 to 3.13.1

Bumps [keras](https://github.com/keras-team/keras) from 3.9.2 to 3.13.1.
- [Release notes](https://github.com/keras-team/keras/releases)
- [Commits](keras-team/keras@v3.9.2...v3.13.1)

---
updated-dependencies:
- dependency-name: keras
  dependency-version: 3.13.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements.txt

@@ -39,7 +39,7 @@ jaxlib==0.8.2
 jaxtyping==0.3.1
 Jinja2==3.1.6
 kagglehub==0.3.11
-keras==3.9.2
+keras==3.13.1
 keras-hub==0.20.0
 libclang==18.1.1
 libcst==1.7.0