[3.12] Correct timedelta description (GH-101417) (GH-114938)

It only represents the difference between two datetime or
date objects, not between two time objects.
(cherry picked from commit 73d20ca)

Co-authored-by: John Belmonte <[email protected]>

Author: miss-islington

Doc/library/datetime.rst

@@ -130,8 +130,8 @@ Available Types
 .. class:: timedelta
    :noindex:
 
-   A duration expressing the difference between two :class:`date`, :class:`.time`,
-   or :class:`.datetime` instances to microsecond resolution.
+   A duration expressing the difference between two :class:`.datetime`
+   or :class:`date` instances to microsecond resolution.
 
 
 .. class:: tzinfo
@@ -203,7 +203,7 @@ objects.
 --------------------------
 
 A :class:`timedelta` object represents a duration, the difference between two
-dates or times.
+:class:`.datetime` or :class:`date` instances.
 
 .. class:: timedelta(days=0, seconds=0, microseconds=0, milliseconds=0, minutes=0, hours=0, weeks=0)