add permissions.yml, update checkout action ver

Author: aptalca

.github/workflows/BuildImage.yml

@@ -11,7 +11,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2.3.3
+      - uses: actions/checkout@v3.1.0
 
       - name: Build image
         run: |

.github/workflows/permissions.yml

@@ -0,0 +1,9 @@
+name: Permission check
+on:
+  pull_request:
+    paths:
+      - '**/run'
+      - '**/finish'
+jobs:
+  permission_check:
+    uses: linuxserver/github-workflows/.github/workflows/init-svc-executable-permissions.yml@v1