Bump jax from 0.4.14 to 0.4.21

Bumps [jax](https://github.com/google/jax) from 0.4.14 to 0.4.21.
- [Release notes](https://github.com/google/jax/releases)
- [Changelog](https://github.com/google/jax/blob/main/CHANGELOG.md)
- [Commits](jax-ml/jax@jax-v0.4.14...jax-v0.4.21)

---
updated-dependencies:
- dependency-name: jax
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

requirements_jax.txt

@@ -1 +1 @@
-jax==0.4.14
+jax==0.4.21