[Swagger]Fix Error

src/api/endpoints/auth/session/generate.js

@@ -32,7 +32,7 @@ import AuthSess from '../../../models/auth-session';
  *             url:
  *               type: string
  *               description: Authentication form's URL
- *       400:
+ *       default:
  *         description: Failed
  *         schema:
  *           $ref: "#/definitions/Error"

src/api/endpoints/auth/session/show.js

@@ -40,7 +40,7 @@ import serialize from '../../../serializers/auth-session';
  *               description: de
  *             app:
  *               $ref: "#/definitions/Application"
- *       400:
+ *       default:
  *         description: Failed
  *         schema:
  *           $ref: "#/definitions/Error"

src/api/endpoints/auth/session/userkey.js

@@ -38,7 +38,7 @@ import serialize from '../../../serializers/user';
  *               description: User Key
  *             user:
  *               $ref: "#/definitions/User"
- *       400:
+ *       default:
  *         description: Failed
  *         schema:
  *           $ref: "#/definitions/Error"