test: add unit test for SERVER_PORT type cast (#438)

Author: DeepDiver1975

tests/OpenIDConnectClientTest.php

@@ -58,7 +58,11 @@ public function testGetRedirectURL()
 
         $_SERVER['SERVER_NAME'] = 'domain.test';
         $_SERVER['REQUEST_URI'] = '/path/index.php?foo=bar&baz#fragment';
+        $_SERVER['SERVER_PORT'] = '443';
         self::assertSame('http://domain.test/path/index.php', $client->getRedirectURL());
+
+        $_SERVER['SERVER_PORT'] = '8888';
+        self::assertSame('http://domain.test:8888/path/index.php', $client->getRedirectURL());
     }
 
     public function testAuthenticateDoesNotThrowExceptionIfClaimsIsMissingNonce()