docs: public void setTransitGatewayAttachmentPropagations(java.util.Collection<TransitGatewayAttachmentPropagation> transitGatewayAttachmentPropagations) {
          if (transitGatewayAttachmentPropagations == null) {
              this.transitGatewayAttachmentPropagations = null;
              return;
          }
  
          this.transitGatewayAttachmentPropagations = new com.amazonaws.internal.SdkInternalList<TransitGatewayAttachmentPropagation>(
                  transitGatewayAttachmentPropagations);
      }