less dupes, cleanup

[TriplEight]

• less dupes:
  &name is called "the yaml anchor", and used to reduce dupes, like that:

jobname:          &name
  stage:          test
  variables:
    var1:         1
  script:
    - do that

another-jobname:
  # it is the same as "jobname`, but the script is different
  <<:   *name
  script:
    - do this

[bkchr]

Why do we do this here? And not in the build substrate job above?

[TriplEight]

you're right, right now it's not effective to split these jobs

[TriplEight]

actually, we are compiling it right there: https://gitlab.parity.io/parity/substrate/-/jobs/339822#L706 , during cargo build.
Can we use that artifact?

[bkchr]

I was speaking about the docker file. Putting the node template into its own job sounds reasonable.

[gabreal]

lgtm