Bump keras from 3.9.0 to 3.12.0

Bumps [keras](https://github.com/keras-team/keras) from 3.9.0 to 3.12.0.
- [Release notes](https://github.com/keras-team/keras/releases)
- [Commits](keras-team/keras@v3.9.0...v3.12.0)

---
updated-dependencies:
- dependency-name: keras
  dependency-version: 3.12.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements.txt

@@ -17,7 +17,7 @@ identify==1.4.5
 importlib-metadata==0.18
 importlib-resources==1.0.2
 joblib==1.2.0
-Keras==3.9.0
+Keras==3.12.0
 Keras-Applications==1.0.8
 Keras-Preprocessing==1.1.0
 kiwisolver==1.1.0