move timing set default value of fileUploadType

src/server/service/config-loader.js

@@ -27,7 +27,7 @@ const ENV_VAR_NAME_TO_CONFIG_INFO = {
     ns:      'crowi',
     key:     'app:fileUploadType',
     type:    TYPES.STRING,
-    default: null,
+    default: 'aws',
   },
   // HACKMD_URI: {
   //   ns:      ,

src/server/service/file-uploader/index.js

@@ -14,7 +14,7 @@ const envToModuleMappings = {
 class FileUploadServiceFactory {
 
   initializeUploader(crowi) {
-    const method = envToModuleMappings[crowi.configManager.getConfig('crowi', 'app:fileUploadType')] || 'aws';
+    const method = envToModuleMappings[crowi.configManager.getConfig('crowi', 'app:fileUploadType')];
     const modulePath = `./${method}`;
     this.uploader = require(modulePath)(crowi);