Reword aware/naive introduction sentence (GH-20175)

This is more informative and avoids the question of whether the period should go inside or outside the quotation marks.

See also GH-20007.
(cherry picked from commit 2e76820)

Co-authored-by: Mathieu Dupuy <mathieu.dupuy@doctolib.com>

Author: miss-islington

Doc/library/datetime.rst

@@ -35,7 +35,8 @@ on efficient attribute extraction for output formatting and manipulation.
 Aware and Naive Objects
 -----------------------
 
-Date and time objects may be categorized as "aware" or "naive".
+Date and time objects may be categorized as "aware" or "naive" depending on
+whether or not they include timezone information.
 
 With sufficient knowledge of applicable algorithmic and political time
 adjustments, such as time zone and daylight saving time information,