Land rapid7#2189, @wchen-r7's fix for [TestRM rapid7#8279]

Author: jvazquez-r7

modules/auxiliary/scanner/http/http_login.rb

@@ -86,7 +86,7 @@ def find_auth_uri
 			return path
 		end
 
-		return path
+		return nil
 	end
 
 	def target_url