BUILDX_GIT_LABELS= or BUILDX_GIT_LABELS=0 don't deactivate git labels

[dgageot]

I'm trying to deactivate the behaviour triggered by BUILDX_GIT_LABELS=1.
I though BUILDX_GIT_LABELS=0 or BUILDX_GIT_LABELS= would work but in fact only unset BUILDX_GIT_LABELS works.

I some contexts, it's hard to unset an env variable but very easy to set its value to 0 or empty string. E.g. when running docker buildx build with go's exec.Command()