[polari/ci] ci: Test flatpak-builder config

[Gitlab System User <gitlab src gnome org>]

commit 1fa845d468c34652de02f93098a2272f81971446
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu Oct 19 07:19:32 2017 +0200

    ci: Test flatpak-builder config
    
    Probably won't work ...

 .gitlab-ci.yml | 15 +++------------
 1 file changed, 3 insertions(+), 12 deletions(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index dc2f35f..50979c0 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,15 +1,6 @@
-image: fedora:26
+image: alexl/flatpak-builder-gnome:3.26
 
-stages:
- - build
-
-before_script:
-  - dnf install -y gcc meson ninja-build redhat-rpm-config gettext itstool
-                   gtk3-devel gjs-devel gobject-introspection-devel
-                   telepathy-glib-devel libappstream-glib desktop-file-utils
-
-build-polari:
+build:
   stage: build
   script:
-    - meson _build .
-    - ninja -C _build test install
+    - flatpak-builder --force-clean --repo=repo app flatpak/org.gnome.Polari.json