fix(#132): tests image

.gitlab-ci.yml

@@ -129,6 +129,7 @@ build_release_tag:
 
 tests:
   stage: tests
+  image: rust:1-bullseye
   rules:
     - if: $CI_COMMIT_REF_NAME =~ /^wip*$/
       when: manual
@@ -136,6 +137,7 @@ tests:
       when: never
     - if: '$CI_MERGE_REQUEST_ID || $CI_COMMIT_BRANCH == "master"'
       when: manual
+    - when always
   script:
     # cargo build is required for cucumber tests anyway
     - cargo build