Support TPU V5e, V6e

[jzxu]

Hello,

I use xmanager to launch TPU inference jobs on Vertex AI. Currently xmanager only supports TPU_V2 and TPU_V3:

xmanager/xmanager/xm/resources.py

Line 81 in dd61e33

# TPUs

Recently I am having trouble getting quota for these, and it sounds like people are being encouraged to move to TPU_V5E or TPU_V6E. Are there any plans to support these newer TPUs on the roadmap?

Thanks,
Joseph