The goal is to reduce the overall wall clock time of our test builds.
This secondary Linux target uses the no-sudo container setup with a Qt
5.10.1 backport and tests the build without BT support as well as the
mobile build (but not the full desktop build and doesn't create an
AppImage as the pre-built Qt5.10.1 is missing QtWebKit).
In exchange we remove the no-bt and mobile build from the existing linux
target.
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
