Update jax requirement from <0.2.19 to <0.2.20 (#521)

Updates the requirements on [jax](https://github.com/google/jax) to permit the latest version.
- [Release notes](https://github.com/google/jax/releases)
- [Changelog](https://github.com/google/jax/blob/main/CHANGELOG.md)
- [Commits](jax-ml/jax@jaxlib-v0.1.32...jax-v0.2.19)

---
updated-dependencies:
- dependency-name: jax
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Jonathan Wenger <[email protected]>

setup.cfg

@@ -57,7 +57,7 @@ exclude =
 
 # Autodiff backends
 jax =
-    jax<0.2.19; platform_system!="Windows"
+    jax<0.2.20; platform_system!="Windows"
     jaxlib<0.1.71; platform_system!="Windows"
 
 # Problem zoo dependencies