buildx failed with: ERROR: invalid tag "ghcr.io/test-kitchen/dokken/:nightly": invalid reference format

buildx failed with: ERROR: failed to solve: process "/bin/sh -c zypper update -y && zypper install -y aaa_base aaa_base-extras ca-certificates cron curl dmidecode e2fsprogs file findutils glibc-locale grep gzip hostname insserv-compat iproute2 iputils less lsb-release ncurses-devel net-tools netcat perl-Getopt-Long-Descriptive sudo systemd systemd-sysvinit sysvinit-tools tar time timezone traceroute util-linux vim wget which && zypper clean && rm -rf /var/log/* && find /etc/systemd/system /usr/lib/systemd/system -path '*.wants/*' \\( -name '*getty*' -or -name '*systemd-logind*' -or -name '*systemd-vconsole-setup*' -or -name '*systemd-readahead*' -or -name '*udev*' \\) -exec rm -v {} \\; && systemctl set-default multi-user.target && systemctl mask dev-hugepages.mount sys-fs-fuse-connections.mount network.service" did not complete successfully: exit code: 106