Avoid raw string in device_tracker source_type (#126601)

homeassistant/components/device_tracker/config_entry.py

@@ -181,7 +181,7 @@ class BaseTrackerEntity(Entity):
         return None
 
     @property
-    def source_type(self) -> SourceType | str:
+    def source_type(self) -> SourceType:
         """Return the source type, eg gps or router, of the device."""
         if hasattr(self, "_attr_source_type"):
             return self._attr_source_type

pylint/plugins/hass_enforce_type_hints.py

@@ -1318,7 +1318,7 @@ _INHERITANCE_MATCH: dict[str, list[ClassTypeHintMatch]] = {
                 ),
                 TypeHintMatch(
                     function_name="source_type",
-                    return_type=["SourceType", "str"],
+                    return_type="SourceType",
                 ),
             ],
         ),