Bug#816448: debcheck: Does not support build-profiles

[Rebecca N. Palmer]

Control: tags -1 patch

If you'd prefer to just fix this without (for now) the broader rewrite, 
https://salsa.debian.org/qa/qa/-/merge_requests/28 claims to do so; I 
haven't tried it but it looks plausible.

Weirdly, this bug doesn't seem to affect everything with build profiles: 
of my packages, snakemake, pandas and statsmodels all have profile 
build-depends, but only snakemake is affected.