set the development ruby version automatically
Revert "Up version of html-pipeline-gitlab."

This reverts commit 17835f095fb10168d5d2f6b2fd4c136844c2bfd1.
Merge branch 'ruby-version' into 'master'

Ruby version

I set it to the latest ruby stable version, that in my experience works without issues.

/cc @jw

See merge request !1163