Switch to macos-13 for Coverity

Apparently `macos-latest-large` is only available for payed accounts.

Author: Youw

.github/workflows/checks.yml

@@ -71,7 +71,7 @@ jobs:
 
 
   coverity-macos:
-    runs-on: macos-latest-large
+    runs-on: macos-13
     needs: [coverity-windows]
 
     steps: