Doc: move a dot outside double quotes (GH-20007)

(cherry picked from commit 4eba677)

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

Author: miss-islington

Doc/library/datetime.rst

@@ -35,7 +35,7 @@ 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".
 
 With sufficient knowledge of applicable algorithmic and political time
 adjustments, such as time zone and daylight saving time information,