fix(specs): body is not required in multiple batch request (#3454)

Author: kai687

specs/search/paths/objects/multipleBatch.yml

@@ -34,7 +34,6 @@ post:
                     $ref: '../../../common/parameters.yml#/indexName'
                 required:
                   - action
-                  - body
                   - indexName
           required:
             - requests