[Bugfix] Optimized exception throwing when stream captures exception (#3322)

### What this PR does / why we need it?
Optimized exception throwing when stream captures exception, resolved
possible misleading.

- vLLM version: v0.11.0rc3
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.0

Signed-off-by: lilinsiman <lilinsiman@gmail.com>

vllm_ascend/worker/model_runner_v1.py

@@ -20,6 +20,7 @@
 import copy
 import gc
 import itertools
+import re
 import time
 from collections import defaultdict
 from collections.abc import Iterator
@@ -3393,6 +3394,14 @@ class NPUModelRunner(LoRAModelRunnerMixin):
                         aclgraph_runtime_mode=aclgraph_runtime_mode,
                         uniform_decode=False)
                 except Exception as e:
+                    error_msg = str(e)
+                    error_code = '0x7020023'
+                    pattern = r'retCode=([^,\s\.]+)'
+                    match = re.search(pattern, error_msg)
+                    if match:
+                        retCode = match.group(1)
+                    # Determine whether the error message is caused by stream capture failure.
+                    if match and retCode == error_code:
                         logger.error(
                             f"ACLgraph sizes capture fail: {type(e).__name__}:\n"
                             "ACLgraph has insufficient available streams to capture the configured number of sizes. "