Removed httpbin.org link which is mentioned 3 times in README

Signed-off-by: Phani Kiran Thaticharla <t.phani.kiran@gmail.com>

Author: phanikiranthaticharla

README.md

@@ -16,7 +16,6 @@ See http://httpbin.org for more information.
 
 ## SEE ALSO
 
-- http://httpbin.org
 - http://requestb.in
 - http://python-requests.org
 - https://grpcb.in/