[UT][NPU] add NPU attention unit tests for ascend_backend and ascend_dsv4_backend (#32294)

test/run_suite.py

@@ -99,6 +99,7 @@ PER_COMMIT_SUITES = {
     ],
     HWBackend.NPU: [
         "base-a-test-1-gpu-small",
+        "stage-a-unit-test-npu",
         "stage-b-test-1-npu-a2",
         "stage-b-test-2-npu-a2",
         "stage-b-test-4-npu-a3",
@@ -337,6 +338,7 @@ def run_a_suite(args):
         if not f.endswith("/conftest.py")
         and not f.endswith("/__init__.py")
         and not f.endswith("/cpu/utils.py")
+        and not f.endswith("/run_tests.py")
     ]
 
     # Strict: all discovered files must have proper registration