add an accessor for the Condition of an Action

Signed-off-by: William Woodall <william@osrfoundation.org>

launch/launch/action.py

@@ -44,6 +44,11 @@ def __init__(self, *, condition: Optional[Condition] = None) -> None:
         """
         self.__condition = condition
 
+    @property
+    def condition(self) -> Optional[Condition]:
+        """Getter for condition."""
+        return self.__condition
+
     def describe(self) -> Text:
         """Return a description of this Action."""
         return self.__repr__()