Use port from options

We don't care too much about the port in testing. Using the port in the options allows us to test against ApacheDS and OpenLDAP without adding any additional conditionals.

test/ldap_test.rb

@@ -10,17 +10,17 @@ module GitHubLdapTestCases
   end
 
   def test_connection_with_list_of_hosts_with_one_valid_host
-    ldap = GitHub::Ldap.new(options.merge(hosts: [["localhost", 3897]]))
+    ldap = GitHub::Ldap.new(options.merge(hosts: [["localhost", options[:port]]]))
     assert ldap.test_connection, "Ldap connection expected to succeed"
   end
 
   def test_connection_with_list_of_hosts_with_first_valid
-    ldap = GitHub::Ldap.new(options.merge(hosts: [["localhost", 3897], ["invalid.local", 3897]]))
+    ldap = GitHub::Ldap.new(options.merge(hosts: [["localhost", options[:port]], ["invalid.local", options[:port]]]))
     assert ldap.test_connection, "Ldap connection expected to succeed"
   end
 
   def test_connection_with_list_of_hosts_with_first_invalid
-    ldap = GitHub::Ldap.new(options.merge(hosts: [["invalid.local", 3897], ["localhost", 3897]]))
+    ldap = GitHub::Ldap.new(options.merge(hosts: [["invalid.local", options[:port]], ["localhost", options[:port]]]))
     assert ldap.test_connection, "Ldap connection expected to succeed"
   end