[MM][Bugfix] Update hf_config to hf_text_config (#5319)

### What this PR does / why we need it?

Following https://github.com/vllm-project/vllm-ascend/pull/5205, update
`hf_config` to `hf_text_config`.

Find more details at
https://github.com/vllm-project/vllm-ascend/pull/5205#issuecomment-3675417534
and
https://github.com/vllm-project/vllm-ascend/pull/5205#issuecomment-3677920872.

### Does this PR introduce _any_ user-facing change?

### How was this patch tested?

- vLLM version: release/v0.13.0
- vLLM main:
5fbfa8d9ef

Signed-off-by: shen-shanshan <467638484@qq.com>

tests/ut/core/test_scheduler_dynamic_batch.py

@@ -130,8 +130,8 @@ class TestSchedulerDynamicBatch(TestBase):
         )
         model_config.pooler_config = MagicMock()
         model_config.multimodal_config = MagicMock()
-        model_config.hf_config = MagicMock()
-        model_config.hf_config.is_encoder_decoder = False
+        model_config.hf_text_config = MagicMock()
+        model_config.hf_text_config.is_encoder_decoder = False
         # Cache config, optionally force APC
         kwargs_cache: Dict[str,
                            Any] = ({} if ENABLE_PREFIX_CACHING is None else {