[gimp] desktop: reenable validity tests for appdata file.

[Jehan <jehanp src gnome org>]

commit f83271a39b19bc52a88c6bc66df99d519498e340
Author: Jehan <jehan girinstud io>
Date:   Wed Jan 23 23:03:36 2019 +0100

    desktop: reenable validity tests for appdata file.
    
    It got disabled in commit 0492157dd2 because of a bug in appstream-util,
    which has been fixed for monthes now. Let's just reenable it and assume
    anyone who wants to run a `make check` on GIMP uses a recent
    distribution with up-to-date system tools.

 desktop/test-appdata.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/desktop/test-appdata.sh b/desktop/test-appdata.sh
index b6735e692f..d4bb50a9c1 100755
--- a/desktop/test-appdata.sh
+++ b/desktop/test-appdata.sh
@@ -2,5 +2,5 @@
 
 # TODO: use validate-strict when the last errors for a strict validation
 # are fixed.
-# appstream-util validate-relax ${GIMP_TESTING_ABS_TOP_BUILDDIR}/desktop/org.gimp.GIMP.appdata.xml && \
+appstream-util validate-relax ${GIMP_TESTING_ABS_TOP_BUILDDIR}/desktop/org.gimp.GIMP.appdata.xml && \
 appstream-util validate-relax ${GIMP_TESTING_ABS_TOP_BUILDDIR}/desktop/gimp-data-extras.metainfo.xml