Updated the return type section of to_datetime (#42244)

* Updated the return type section of to_datetime to include list-like mixed timezone inputs

* updated the Returns section

* updated the Return section as suggested by mroeschke

* removed the extra line in my previous commit

* Update pandas/core/tools/datetimes.py

Co-authored-by: Sylvain Marié <[email protected]>

Co-authored-by: Sylvain Marié <[email protected]>

Author: prabha-git

pandas/core/tools/datetimes.py

@@ -762,7 +762,9 @@ def to_datetime(
         If parsing succeeded.
         Return type depends on input:
 
-        - list-like: DatetimeIndex
+        - list-like:
+            - DatetimeIndex, if timezone naive or aware with the same timezone
+            - Index of object dtype, if timezone aware with mixed time offsets
         - Series: Series of datetime64 dtype
         - scalar: Timestamp