The pkgconfig file in Debian and Ubuntu is definitely broken and we've
reported it upstream, but we don't really want to keep our image building
failing while we wait for that to be fixed.
Skip the auto/pkgconfig test if both: a) we're on Ubuntu, and b) the .pc
checksum matches a known-bad copy. I'm also CC'd to the bug to catch if it
gets fixed.
Bug: https://bugs.debian.org/1078026