[gnome-calculator/ci-screenshots] Run gnome-calculator in background

[Robert Roth <robertroth src gnome org>]

commit ae238f87d193e2220f1762d5ac63a394e140eab6
Author: Robert Roth <robert roth off gmail com>
Date:   Sat Jul 14 22:01:33 2018 +0300

    Run gnome-calculator in background

 .gitlab-ci.yml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 26745e9a..5b21ab0a 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -16,10 +16,12 @@ build-fedora:
     - ninja -C _build install
     - Xvfb -fp /usr/share/X11/fonts/misc :0 -screen 0 1280x1024x24&
     - sleep 5
-    - DISPLAY=:0 _build/src/gnome-calculator
+    - DISPLAY=:0 _build/src/gnome-calculator&
     - sleep 5
     - DISPLAY=:0 import -window root screenshot.jpg
     - sleep 5
+    - pkill gnome-calculator
+    - pkill Xvfb
   artifacts:
     paths:
     - screenshot.jpg