Speed up update_weights_from_tensor

[fzyzcjy]

Motivation

Speed up by avoiding tensor serialization and deserialization. Since it was only used for tests before and never released, the old one was OK, and the new one with API breaking changes seems OK.

Modifications

Checklist

• Format your code according to the Contributor Guide.
• Add unit tests as outlined in the Contributor Guide.
• Update documentation as needed, including docstrings or example tutorials.

[fzyzcjy]

CI looks green now

[fzyzcjy]

Hmm, quick question firstly: is it possible this is flakyness? Commit 5867d7a fails accuracy-test-2, while 8f8c9c1 (same logic) fails accuracy-test-1. And the failures does not seem to be super related to the current PR at first glance.

[merrymercy]

@fzyzcjy Yes, some these are flaky.

[fzyzcjy]

I see