Note: It is unfortunate that the buildds themselves also have non-build-essential packages in their chroots. I would expect this will be eventually fixed after the release of trixie, as they will probably switch to the stable version of debootstrap in all architectures (currently, arch:all packages like this one are built on amd64, for which the old debootstrap is still used afaik).
I wish we could fix this mismatch in Salsa CI before that. The more chroots match the official definition of build-essential, the better, as bugs like this one will be easier to diagnose. Thanks.