[XlaCallModule] Drop support for dim_args_spec attribute.

This attribute was used to support shape polymorphism in versions
up to and including version 4. Starting on March 28th 2023 with
JAX version 0.4.6 we stopped using this attribute. We are now
beyond the 6 month backward compatibility version and we drop
support for this attribute.

We also increase the minimum supported serialization version to 5.
See https://github.com/google/jax/blob/main/jax/experimental/jax2tf/README.md#native-serialization-versions

PiperOrigin-RevId: 574450204

Author: gnecula

jax/experimental/jax2tf/README.md

@@ -810,6 +810,8 @@ We list here a history of the serialization version numbers:
     launch.
     Used in JAX from March 15, 2023 (cl/516885716). Starting with
     March 28th, 2023 we stopped using `dim_args_spec` (cl/520033493).
+    The support for this version was dropped on
+    October 17th, 2023 (cl/573858283).
   * Version 5 adds support for `call_tf_graph`. This is currently used
     for some specialized use cases. Used in JAX from May 3rd, 2023
     (cl/529106145).