Merge branch 'feature/sles151' into 'master'

Drop SLES v15.1

See merge request !8

.gitlab-ci.yml

@@ -62,23 +62,6 @@ upload/SUSE/15.2:
   dependencies:
     - build/sles/15.2
 
-build/sles/15.1:
-  <<: *build
-  variables:
-    DOCKER_IMAGE: sles/15.1
-
-test/sles/15.1:
-  <<: *test
-  variables:
-    DOCKER_IMAGE: sles/15.1
-  dependencies:
-    - build/sles/15.1
-
-upload/SUSE/15.1:
-  <<: *upload
-  dependencies:
-    - build/sles/15.1
-
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 # openSUSE
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