gist-logs: remove unnecessary exception class

Library/Contributions/cmd/brew-gist-logs.rb

@@ -79,7 +79,7 @@ def post path, data
   end
   request.body = Utils::JSON.dump(data)
   response = http.request(request)
-  raise HTTP_Error, response if response.code != '201'
+  raise "HTTP #{response.code} #{response.message}" if response.code != "201"
 
   if !response.body.respond_to?(:force_encoding)
     body = response.body
@@ -92,12 +92,6 @@ def post path, data
   Utils::JSON.load(body)
 end
 
-class HTTP_Error < RuntimeError
-  def initialize response
-    super "HTTP #{response.code} #{response.message}"
-  end
-end
-
 def usage
   puts "usage: brew gist-logs [options] <formula>"
   puts