[simple-scan] Fix CI dependency installing waiting for prompts

[Robert Ancell <rancell src gnome org>]

commit d6282bd270bf1275ca86b4fc1abcb74779c95d5f
Author: Robert Ancell <robert ancell canonical com>
Date:   Thu Dec 7 10:09:15 2017 +1300

    Fix CI dependency installing waiting for prompts

 .gitlab-ci.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 3830bf3..71aa230 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -4,8 +4,8 @@ stages:
  - build
 
 before_script:
-  - apt update
-  - apt install meson valac libgtk-3-dev libgusb-dev libcolord-dev libpackagekit-glib2-dev libwebp-dev 
libsane-dev gettext itstool
+  - apt-get update
+  - apt-get install -q -y meson valac libgtk-3-dev libgusb-dev libcolord-dev libpackagekit-glib2-dev 
libwebp-dev libsane-dev gettext itstool
 
 build-simple-scan:
   stage: build