build: Switch to debian:unstable Docker image

We have a restricted enough amount of dependencies that relying on
Debian unstable seems safe. More than using debian:testing which might
end up stuck with problems for some time until packages migrate from
unstable.

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 72b7625c888df04b5e713a9ab19e1d4b1422a8e4..a90cfc031903bcf77b05dc1238d99ec1745c649d 100644 (file)
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -24,7 +24,7 @@
   coverage: /^TOTAL.*\s+(\d+\%)$/
 
 .debian:
-  image: debian:latest
+  image: debian:unstable
   stage: test
   before_script:
     - apt-get update -qq