gitlab: run unit tests in i686 cross build
gitlab: run unit tests in i686 cross build

In most cross builds we can't run tests since we can't assume QEMU user
mode emulators are loaded. i686 is special though because x86_64 can run
i686 natively, so we should run unit tests there.

The key benefit is that this gives us 32-bit unit test coverage in CI.

Reviewed-by: Erik Skultety <2c14d38fa47c8799f1b9c16280abe27f8edfec6e@redhat.com>
Signed-off-by: Daniel P. Berrangé <bb938cf255e055ff3507f2627d214e8e62118fcf@redhat.com>

zippy2/libvirt,nertpinx/libvirt,zippy2/libvirt,jfehlig/libvirt,olafhering/libvirt,libvirt/libvirt,crobinso/libvirt,zippy2/libvirt,nertpinx/libvirt,crobinso/libvirt,libvirt/libvirt,nertpinx/libvirt,zippy2/libvirt,nertpinx/libvirt,jfehlig/libvirt,libvirt/libvirt,nertpinx/libvirt,libvirt/libvirt,olafhering/libvirt,jfehlig/libvirt,crobinso/libvirt,crobinso/libvirt,jfehlig/libvirt,olafhering/libvirt,olafhering/libvirt