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