Update zashi-tests.yml

Author: LukasKorba

.github/workflows/zashi-tests.yml

@@ -9,10 +9,10 @@ jobs:
     permissions:
           contents: read
 
-    runs-on: macos-latest
+    runs-on: macos-13
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
       timeout-minutes: 1
 
     - name: Select Xcode version