ci: Workaround an issue with GLib on Fedora 30

This remove this error running test-listen test on a Fedora 30 docker
image:

(/builds/spice/spice/build/server/tests/test-listen:2233): GLib-GIO-CRITICAL **: 15:29:03.123: g_file_new_for_path: assertion 'path != NULL' failed

This error is due to some missing configuration on the image.
On a fully installed Desktop/Server machine these configuration
are usually in place so you won't note the issue but on recent
docker images these configuration are missing.

Running the dconf command add required configuration.

Signed-off-by: Frediano Ziglio <fziglio@redhat.com>
Acked-by: Uri Lublin <uril@redhat.com>

.gitlab-ci.yml

@@ -8,9 +8,16 @@ before_script:
     glib2-devel celt051-devel pixman-devel alsa-lib-devel openssl-devel libjpeg-turbo-devel
     libcacard-devel cyrus-sasl-devel lz4-devel opus-devel
     gstreamer1-devel gstreamer1-plugins-base-devel
+    dconf
     -y
   - git clone ${CI_REPOSITORY_URL/spice.git/spice-protocol.git}
   - (cd spice-protocol && ./autogen.sh --prefix=/usr && make install)
+  # This is a workaround for Fedora docker image, this will add some
+  # missing configuration
+  # '/org/gnome/system/location/enabled' is just the first key path
+  # I found, nothing special in it
+  # TODO remove when the image will fix this issue
+  - dconf reset /org/gnome/system/location/enabled || true
 
 makecheck:
   script: