fix: convert process wrong type

close #45

Author: sabakugaara

src/Upyun/Upyun.php

@@ -377,7 +377,7 @@ public function process($tasks, $type, $source = '')
             case self::$PROCESS_TYPE_SYNC_FILE:
                 $options['app_name'] = 'spiderman';
                 break;
-            case self::$PROCESS_TYPE_SYNC_FILE:
+            case self::$PROCESS_TYPE_CONVERT:
                 $options['app_name'] = 'uconvert';
                 break;
             case self::$PROCESS_TYPE_STITCH: