Remove invalid opcache test (doublon)

Author: herewithme

phpwpinfo.php

@@ -235,7 +235,6 @@ public function test_php_extensions() {
 			'apcu'      => 'info',
 			'memcache'  => 'info',		// TO DELETE? (Not in handbook)
 			'memcached' => 'info',
-			'opcache'   => 'info',
 			'redis'     => 'info',
 			// Others
 			'ftp'       => 'info',