Stop building packages for OpenSUSE 42.1 as it is discontinued

OpenSUSE 42.1 has been discontinued on May 17 and we are finding building of docker builder image failing due to unavailable repositories. We should probably announce discontinuing it and provide package for OpenSUSE LEAP 42.2 as it is the current release version. We will have to

1. Announce 9.3 to be the last version for OpenSUSE 42.1 in blog post
2. Remove OpenSUSE42.1 jobs from .gitlab-ci.yml
3. Create builder image for OpenSUSE 42.2
4. Add test/build jobs to .gitlab-ci.yml

/cc @gitlab-build-team @joshlambert