DOC: Fix validation error RT01 for itertuples function (pandas-dev#25356)

Change yield to return

Author: ihsansecer

pandas/core/frame.py

@@ -839,12 +839,12 @@ def itertuples(self, index=True, name="Pandas"):
             The name of the returned namedtuples or None to return regular
             tuples.
 
-        Yields
+        Returns
         -------
-        collections.namedtuple
-            Yields a namedtuple for each row in the DataFrame with the first
-            field possibly being the index and following fields being the
-            column values.
+        iterator
+            An object to iterate over namedtuples for each row in the
+            DataFrame with the first field possibly being the index and
+            following fields being the column values.
 
         See Also
         --------