feat: add mtp ut and fix some bugs (#2453)

### What this PR does / why we need it?
Fix mtp mode ut

### Does this PR introduce _any_ user-facing change?
Nothing

### How was this patch tested?
This can be tested in the same way as a unit test.


- vLLM version: v0.10.0
- vLLM main:
53415653ff

Signed-off-by: 赵江江 <zhaojiangjiang1@h-partners.com>
Co-authored-by: 赵江江 <zhaojiangjiang1@h-partners.com>

tests/ut/quantization/test_quant_config.py

@@ -113,6 +113,7 @@ class TestAscendQuantConfig(TestBase):
     def test_get_quant_method_for_fused_moe(self):
         fused_moe_layer = MagicMock(spec=FusedMoE)
         fused_moe_layer.moe = MagicMock(spec=FusedMoEConfig)
+        fused_moe_layer.moe_config = MagicMock(spec=FusedMoEConfig)
 
         # Test skipped layer
         with patch.object(self.ascend_config, 'is_layer_skipped_ascend', return_value=True), \