Bump keras from 3.1.1 to 3.8.0

Bumps [keras](https://github.com/keras-team/keras) from 3.1.1 to 3.8.0.
- [Release notes](https://github.com/keras-team/keras/releases)
- [Commits](keras-team/keras@v3.1.1...v3.8.0)

---
updated-dependencies:
- dependency-name: keras
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -1,6 +1,6 @@
 h5py == 3.10.0
 jupyter == 1.0.0
-keras == 3.1.1
+keras == 3.8.0
 matplotlib == 3.8.4
 notebook == 7.1.2
 numpy == 1.26.4