DOC: fix duplicate Returns/Yields in option_context and mark expected warning in timeseries example (GH#61720)

Author: EvMossan

doc/source/user_guide/timeseries.rst

@@ -197,6 +197,7 @@ a ``Series``, this returns a ``Series`` (with the same index), while a list-like
 is converted to a ``DatetimeIndex``:
 
 .. ipython:: python
+    :okwarning:
 
     pd.to_datetime(pd.Series(["Jul 31, 2009", "Jan 10, 2010", None]))
 

pandas/_config/config.py

@@ -462,11 +462,6 @@ def option_context(*args) -> Generator[None]:
         interpreted as (pattern, value) pairs. Alternatively, a single
         dictionary of {pattern: value} may be provided.
 
-    Returns
-    -------
-    None
-        No return value.
-
     Yields
     ------
     None