tests: xfail moe quantization classes mxfp8_bf16 UTs on sm103 (#1754)

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## 📌 Description

Temporarily marking test_trtllm_gen_fused_moe mxfp8_bf16 cases as xfail
until we converge on fix without causing regression on B200.

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---------

Co-authored-by: jimmzhou <[email protected]>

Author: jimmyzho

tests/test_trtllm_gen_fused_moe.py

@@ -2034,6 +2034,17 @@ def test_moe_quantization_classes(
             f"Incompatible: {moe_impl.name} + {weight_processing['use_shuffled_weight']} + {weight_processing['layout']}"
         )
 
+    # TODO(jimmzhou): enable MxFP4xBf16 on SM103
+    if (
+        type(moe_impl) is FP4Moe
+        and moe_impl.quant_mode == QuantMode.FP4_MXFP4_Bf16
+        and compute_capability[0] == 10
+        and compute_capability[1] == 3
+    ):
+        pytest.xfail(
+            "Note(jimmzhou): Make MxFP4xBf16 nonfunctional on SM103 to avoid B200 regression"
+        )
+
     moe_impl._cache_permute_indices = cache_permute_indices
 
     seed = 0