gce-xfstests-bld: fix blocked test-appliance build on GCE

Now that we have included cryptsetup in the packages that should be
included for the test appliance, we need to preset a debconf selection
for the keyboard-configuration package to keep it from blocking the
install.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/kvm-xfstests/test-appliance/gce-xfstests-bld.sh b/kvm-xfstests/test-appliance/gce-xfstests-bld.sh
index c729d95..c162189 100644
--- a/kvm-xfstests/test-appliance/gce-xfstests-bld.sh
+++ b/kvm-xfstests/test-appliance/gce-xfstests-bld.sh
@@ -65,6 +65,7 @@
 debconf-set-selections <<EOF
 kexec-tools	kexec-tools/use_grub_config	boolean	true
 kexec-tools	kexec-tools/load_kexec	boolean	true
+keyboard-configuration	keyboard-configuration/variant	select	English (US)
 EOF
 apt-get install -y $PACKAGES
 apt-get clean