build the Dockerimage used in CI

.gitlab-ci.yml

@@ -5,8 +5,7 @@ stages:
   - test
 
 build docker:
-  stage:
-    - prebuild
+  stage: prebuild
   image:
     name: gcr.io/kaniko-project/executor:debug
     entrypoint: [""]
@@ -25,8 +24,7 @@ build docker:
       - test-requirements.txt
 
 test:
-  stage:
-    - test
+  stage: test
   script:
     - py.test --verbose --cov=adaptive --cov-report term --cov-report html adaptive
   artifacts:
@@ -34,15 +32,13 @@ test:
       - htmlcov
 
 authors check:
-  stage:
-    - test
+  stage: test
   script:
     - MISSING_AUTHORS=$(git shortlog -s HEAD | sed -e "s/^[0-9\t ]*//"| xargs -i sh -c 'grep -q "{}" AUTHORS.md || echo "{} missing from authors"')
     - if [ ! -z "$MISSING_AUTHORS" ]; then { echo $MISSING_AUTHORS; exit 1; }; fi
   allow_failure: true
 
 check whitespace style:
-  stage:
-    - test
+  stage: test
   script: ./check_whitespace
   allow_failure: true