Revert JAX TPU VM to 0.4.23

Latest version seems to fail our tests

Author: djherbis

tpu/config.txt

@@ -6,7 +6,7 @@ PYTHON_VERSION_PATH=python3.10
 TENSORFLOW_VERSION=2.15.0
 TF_LIBTPU_VERSION=1.9.0
 TF_LINUX_WHEEL_VERSION=manylinux_2_17_x86_64.manylinux2014_x86_64
-JAX_VERSION=0.4.26
+JAX_VERSION=0.4.23
 # gsutil ls gs://pytorch-xla-releases/wheels/tpuvm/* | grep libtpu | grep -v -E ".*rc[0-9].*"
 # Supports nightly
 TORCH_VERSION=2.2.0