chore: Make YAML workflow git-based (#7477)

.github/workflows/yaml.yml

@@ -3,10 +3,12 @@ name: YAML Validation
 on:
   pull_request:
     paths:
-      - '**.y?ml'
+      - '**.yml'
+      - '**.yaml'
   push:
     paths:
-      - '**.y?ml'
+      - '**.yml'
+      - '**.yaml'
 
 permissions:
   contents: read # to fetch code (actions/checkout)
@@ -21,4 +23,4 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Run yamllint
-        run: find . -path \*/vendor -prune -false -o -name \*.y*ml | xargs yamllint
+        run: git ls-files --cached -z -- '*.y*ml' | xargs --null -- yamllint