Remove /doc/search redirect

As per discussed in erlang#68 (comment)

Author: eksperimental

_redirects

@@ -8,7 +8,6 @@
 /pipermail/*        https://erlang.org/pipermail/:splat
 
 ## Old removed URLs
-/doc/search         /doc
 /docs/versions      /documentation
 /rss/news/*           /news.xml
 /erlang-enhancement-proposals/home.html /eeps/