[gegl] gitlab-ci: Reuse ccache between builds

[Øyvind "pippin" Kolås <ok src gnome org>]

commit 2324be2820939a399305e7e2f1c59b4acabb688e
Author: Jan Vesely <jano vesely gmail com>
Date:   Fri Feb 21 18:37:48 2020 -0500

    gitlab-ci: Reuse ccache between builds
    
    Use ccache in babl builds.
    Signed-off-by: Jan Vesely <jano vesely gmail com>

 .gitlab-ci.yml | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 0740a3595..f2ace52f1 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -5,10 +5,13 @@ stages:
 variables:
   BABL_DIR: "_babl_install"
   BABL_PREFIX: "$CI_PROJECT_DIR/$BABL_DIR"
+  CCACHE_DIR: "$CI_PROJECT_DIR/.ccache"
 
 cache:
+  key: ${CI_JOB_NAME}
   paths:
   - _pacman_cache
+  - .ccache
 
 image: archlinux/base:latest
 
@@ -20,7 +23,7 @@ image: archlinux/base:latest
   variables:
     GIT_DEPTH: "5"
   before_script:
-    - pacman -Syu --noconfirm --needed --cachedir `pwd`/_pacman_cache git base-devel meson lcms2 
gobject-introspection
+    - pacman -Syu --noconfirm --needed --cachedir `pwd`/_pacman_cache git base-devel ccache meson lcms2 
gobject-introspection
     - git clone --depth=$GIT_DEPTH https://gitlab.gnome.org/GNOME/babl.git _babl
     - cd _babl
     - mkdir _build