docs: public TransitGatewayRoute withTransitGatewayAttachments(TransitGatewayRouteAttachment... transitGatewayAttachments) {
          if (this.transitGatewayAttachments == null) {
              setTransitGatewayAttachments(new com.amazonaws.internal.SdkInternalList<TransitGatewayRouteAttachment>(transitGatewayAttachments.length));
          }
          for (TransitGatewayRouteAttachment ele : transitGatewayAttachments) {
              this.transitGatewayAttachments.add(ele);
          }
          return this;
      }