BTW, I've just rolled back snap spec in master to "core18" base image to the state when it was building successfully. I'm still getting this "built, failed to release" error for all architectures. Most likely due to "package contains external symlinks: bin/python lint-snap-v2_external_symlinks" error. It's very likely all python builds are now broken in snapcraft 4.0.4.
BTW, I've just rolled back snap spec in master to "core18" base image to the state when it was building successfully. I'm still getting this "built, failed to release" error for all architectures. Most likely due to "package contains external symlinks: bin/python lint-snap- v2_external_ symlinks" error. It's very likely all python builds are now broken in snapcraft 4.0.4.