[gegl/wip/schumaml/vala-build] build: add vala to .gitlab-ci.yml to spot any vala-related build problems

[Michael Schumacher <schumaml src gnome org>]

commit bed69154a7a688e21b432e995a290599871fae65
Author: Michael Schumacher <schumaml gmx de>
Date:   Sun Aug 11 13:41:36 2019 +0200

    build: add vala to .gitlab-ci.yml to spot any vala-related build problems

 .gitlab-ci.yml | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 27d6496a1..b52ab7dc5 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -67,6 +67,7 @@ babl-min-meson:
         python
         sdl2
         suitesparse
+        vala
   script:
    - mkdir _build
    - cd _build