buildx failed with: ERROR: failed to build: failed to solve: process "/bin/sh -c sed -i'/flatpak remote-add --user --if-not-exists flathub/a flatpak remote-modify --user flathub --url=https://mirrors.ustc.edu.cn/flathub' /usr/share/org.vanillaos.FirstSetup/vanilla_first_setup/scripts/setup-flatpak-remote && rm -rf /var/cache/debconf /var/cache/ldconfig /var/cache/man /var/log/*" did not complete successfully: exit code: 1