Adding the required base_mlp_dim

[parambole]

Description

Adding the required base_mlp_dim to avoid the error

ValueError: For a fully MoE model, base_mlp_dim must be equal to base_moe_mlp_dim. Received base_mlp_dim=7168 and base_moe_mlp_dim=1536.

Tests

Locally

Checklist

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[gobbleturk]

just noting we should probably have an AOT test for every model to catch things like this