[gnome-user-docs/strict-ci] Enable strict checking with itstool for CI

[David King <davidk src gnome org>]

commit 06770cd1e4d2429fc0459f911457dc5d627ab506
Author: David King <amigadave amigadave com>
Date:   Sat Jul 20 23:08:28 2019 +0100

    Enable strict checking with itstool for CI
    
    Fixes: https://gitlab.gnome.org/GNOME/gnome-user-docs/issues/26

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f422c58b..11c1415a 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -7,6 +7,6 @@ build-fedora:
     - yelp-check links gnome-help/C system-admin-guide/C
     - yelp-check orphans gnome-help/C system-admin-guide/C
     - yelp-check validate gnome-help/C system-admin-guide/C
-    - ./autogen.sh
+    - ./autogen.sh ITSTOOL="/usr/bin/itstool --strict"
     - make
     - make check