Add stapling after notarization

contrib/macos/notarize.py.in

@@ -67,4 +67,10 @@ while not done:
     print("\033[1K\r(+{:d}m{:02d}s) {}: {}".format(mins, secs, st, status), end='', flush=True)
 
 print("\n")
-sys.exit(0 if success else 42)
+if not success:
+    sys.exit(42)
+
+print("Stapling {}".format(pkg))
+result = subprocess.run(['xcrun', 'stapler', 'staple', pkg])
+
+result.check_returncode()