Update macOS to v13 in register-schemas-dryrun.yaml

to try and avoid perpetual "Waiting for a runner to pick up this job..." message

Author: MasterPastures

.github/workflows/register-schemas-dryrun.yaml

@@ -8,7 +8,7 @@ env:
 
 jobs:
   register-schemas-dryrun:
-    runs-on: macos-12
+    runs-on: macos-13
     steps:
       - uses: actions/checkout@v2