[gnome-build-meta] .gitlab-ci.yml: update buildstream to 1.1.6

[Abderrahim Kitouni <akitouni src gnome org>]

commit 67816519ee60e947f7a1b8a467bf519b3d2a2859
Author: Abderrahim Kitouni <akitouni gnome org>
Date:   Sat Aug 18 13:52:53 2018 +0100

    .gitlab-ci.yml: update buildstream to 1.1.6

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index a58ef3b..cdb1d92 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -4,7 +4,7 @@ variables:
   XDG_CACHE_HOME: "${CI_PROJECT_DIR}/cache"
   GET_SOURCES_ATTEMPTS: 3
   BST: "bst --config build.conf --log-file logs/build.log --colors"
-  BST_SHA: '0c57cdda9ee98c9601b2944958338a02dfefcbb8' #  1.1.5
+  BST_SHA: '970c6696f2eef0bde282f82eb95ae4708ccbf308' #  1.1.6
 
 stages:
   - build