gitlab-ci: Don't use Immediate-Configure

This confuses apt like

E: Could not configure 'libc6:i386'. E: Could not perform immediate configuration on 'libgcc-s1:i386'. Please see man 5 apt.conf under APT::Immediate-Configure for details. (2) E: Failed to process build dependencies

and since this is only for a cross architecture it doesn't matter for us.

Signed-off-by: Guido Günther guido.gunther@puri.sm