Merge branch 'updatedocker' into 'NIFTy_7'

After updating build machine use newest docker version again

See merge request ift/nifty!553

.gitlab-ci.yml

@@ -13,7 +13,7 @@ stages:
 build_docker_from_scratch:
   only:
     - schedules
-  image: docker:19.03.8
+  image: docker
   stage: build_docker
   before_script:
     - ls
@@ -25,7 +25,7 @@ build_docker_from_scratch:
 build_docker_from_cache:
   except:
     - schedules
-  image: docker:19.03.8
+  image: docker
   stage: build_docker
   before_script:
     - ls