Big diff: Use new "|" union syntax (#5872)

stdlib/msilib/text.pyi

@@ -1,9 +1,9 @@
 import sys
-from typing import List, Optional, Tuple
+from typing import List, Tuple
 
 if sys.platform == "win32":
 
-    ActionText: List[Tuple[str, str, Optional[str]]]
-    UIText: List[Tuple[str, Optional[str]]]
+    ActionText: List[Tuple[str, str, str | None]]
+    UIText: List[Tuple[str, str | None]]
 
     tables: List[str]