sanity-check: stop allowing os-release ID to be ubuntu

os-release pretended we were Ubuntu for a while, to make packages
with different build steps for Debian and Ubuntu follow Ubuntu-like
code paths. This has now been fixed.

Reviewed-by: Simon McVittie <smcv@collabora.co.uk>
Signed-off-by: Héctor Orón Martínez <hector.oron@collabora.co.uk>
Differential Revision: https://phabricator.apertis.org/D4272

common/sanity-check

@@ -49,10 +49,7 @@ test -S /run/user/$(id -u user)/bus || fail user-bus-is-up
 test -e /etc/debian_version || fail has-debian_version
 cat /etc/os-release || fail os-release
 grep -E '^NAME=("?)Apertis\1$' /etc/os-release || fail os-release-name
-# This should really test for apertis, but that would currently
-# fail - see https://phabricator.apertis.org/T2117 - so they also
-# allow Ubuntu
-grep -E '^ID=("?)(apertis|ubuntu)\1$' /etc/os-release || fail os-release-id
+grep -E '^ID=("?)apertis\1$' /etc/os-release || fail os-release-id
 
 if ! test -S /run/user/$(id -u user)/wayland-0; then
     common/run-test-in-systemd --user=user --name=x11-works -- xterm -e /bin/true