[3.13] Explicitly import urllib.error in urllib.robotparser (GH-1…

…28737) (#128793)

Explicitly import `urllib.error` in `urllib.robotparser` (GH-128737)
(cherry picked from commit 53e8942)

Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>

Lib/urllib/robotparser.py

@@ -11,6 +11,7 @@
 """
 
 import collections
+import urllib.error
 import urllib.parse
 import urllib.request