Rebase index_copy fix

[wonjoolee95]

Rebase @bhavya01's index_copy fix from llama2-google-next-inference branch

[JackCaoG]

@wonjoolee95 can you do a run and see if this change has any performance implication?

[wonjoolee95]

This rebase seems to give me the buffer with shape bf16[1,2048,32,128] on device SPMD:0 is null error (full paste: https://gist.github.com/wonjoolee95/73b1590e9432eabe39697708f8b2da71).

And when we change to openxla (instead of openxla_eval), the performance seems significantly worse.

We can tackle the SPMD inference work and this issue separately. For now, we can either keep using the existing out-of-place .index_copy and manually set the dynamo_cache_hit or use continuing using the 05012024 wheels.

cc @bhavya01