Remove effbot urls (GH-26308)

Objects/stringlib/fastsearch.h

@@ -4,7 +4,8 @@
 
 /* fast search/count implementation, based on a mix between boyer-
    moore and horspool, with a few more bells and whistles on the top.
-   for some more background, see: http://effbot.org/zone/stringlib.htm */
+   for some more background, see:
+   https://web.archive.org/web/20201107074620/http://effbot.org/zone/stringlib.htm */
 
 /* note: fastsearch may access s[n], which isn't a problem when using
    Python's ordinary string types, but may cause problems if you're