Update tokamax group sizes for pipeline

[NuojCheng]

Description

We got tokamax shape error when using pipeline_fsdp_ag_per_repeat=true and model_name=deepseek3-671b-2dfsdp. This PR fixes the error.

Tests

Given branch passes this train compile script.

Checklist

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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