[gimp/wip/Jehan/CI-Windows] Move to Debian testing (TODO: will be rebased).

[Jehan <jehanp src gnome org>]

commit 8f1ebb461d42f6ee4793831e3eab43a3d40aa863
Author: Jehan <jehan girinstud io>
Date:   Wed Sep 25 21:43:55 2019 +0200

    Move to Debian testing (TODO: will be rebased).

 .gitlab-ci.yml | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 438bef546c..e6f308a05a 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -29,15 +29,17 @@ cache:
     paths:
     - "${INSTALL_DIR}"
   before_script:
-    - pacman -Syu --noconfirm --needed --cachedir "${PACMAN_CACHE}"
+    - apt-get update
+    - apt-get install --yes --no-install-recommends
+        build-essential
+        cmake
+        ninja-build
+        ca-certificates
         git
-        base-devel
+        mingw-w64
         python-docutils
-        python-pip
-    - curl https://aur.archlinux.org/cgit/aur.git/snapshot/mingw-w64-gcc.tar.gz --output mingw-w64-gcc.tar.gz
-    - tar xzf mingw-w64-gcc.tar.gz
-    - cd mingw-w64-gcc
-    - makepkg -si
+        python3-pip
+        python3-setuptools
     - pip3 install crossroad
 
 build-git-x86_64-w64-mingw32-meson: