Add 'Ascend NPU' label restrictions

Author: xuedinge233

.github/workflows/build.yml

@@ -1459,15 +1459,16 @@ jobs:
 #          make
 
   openEuler-latest-cmake-cann:
+    if: contains(github.event.pull_request.labels.*.name, 'Ascend NPU')
     defaults:
       run:
        shell: bash -el {0}
     runs-on: ubuntu-latest
 
     strategy:
       matrix:
-        cann: ['openeuler-python3.10-cann8.0.rc3.beta1']
         build: ['Release']
+        cann: ['openeuler-python3.10-cann8.0.rc3.beta1']
         device: ['ascend910b3']
     container:
         image: ascendai/cann:${{ matrix.cann }}