Fix typo in Lib/socketserver.py (GH-17024)

changed 'This is bad class design, but save some typing'
into 'This is bad class design, but saves some typing'.

Lib/socketserver.py

@@ -24,7 +24,7 @@
 
 The classes in this module favor the server type that is simplest to
 write: a synchronous TCP/IP server.  This is bad class design, but
-save some typing.  (There's also the issue that a deep class hierarchy
+saves some typing.  (There's also the issue that a deep class hierarchy
 slows down method lookups.)
 
 There are five classes in an inheritance diagram, four of which represent