[Bug fix #40813] Fix base_model_tp_plan of Starcoder2 model.

[greg-kwasniewski1]

Fixes #40813

Second linear layer in Starcoder2s MLP c_proj should be row-sharded and not column-sharded. Otherwise, column-sharding both c_fc and c_proj results in incorrect sharding and tensor shape mismatch.

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[github-actions]

[For maintainers] Suggested jobs to run (before merge)

run-slow: starcoder2

[Rocketknight1]

cc @Cyrilvallez maybe?

[Cyrilvallez]

Indeed! Should absolutely be rowwise, thanks a lot for the catch!