Use Symfony Request for openid module

Part of #1998638: [Meta] Refactor raw PHP variables (e.g $_SERVER, $_REQUEST, $_GET, $_POST) with Symfony Request object

Files that need converting are:

• core/modules/openid/openid.inc
• core/modules/openid/openid.module
• core/modules/openid/tests/openid_test.module
• core/modules/openid/tests/openid_test.module