Merge branch 'oa' into dev

pkg/model/approval.go

@@ -825,7 +825,7 @@ func getApprovalContentFactory(typeFiled string) (ApprovalContentInterface, erro
 		if TypeMap[typeFiled] == TypeOa {
 			return &ApprovalOA{}, nil
 		} else {
-			return nil, errors.New("无法识别的审批类型")
+			return &Approval{}, nil
 		}
 	}
 }