CI: remove outdated 'docker' tab to run on the new CERN infrastructure

The CERN GitLab CI infrastructure has changed in the latest months, and runners tagged as 'docker' are being phasing out.

To run our jobs on the new infrastrucre we need to remove the code:

tags:
  - docker

In that way, the jobs will land on the new generic runners.

This is the doc about the new infrastructure: https://gitlab.docs.cern.ch/docs/Build%20your%20application/CI-CD/Runners/k8s-shared-runners/

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NOTE We start with the generic runners, to see if they work fine for our use cases. If not, we'll ask for more specific runners.

changed the description

OK, the terminal confirms that we are now using the new runners with Kaniko and Kubernetes:

Cc: @boudreau @tsulaia @jojungge

Apparently, in this migration phase, the use of the old tags: -docker setting can make the CI jobs land on a "no man's land", where they can be lost.

This is what Ismael from the CERN GitLab team told me.

Therefore, this migration to the new infrastructure should fix the problems with our CI.

However, if after this migration we keep seeing failing pipelines, Ismael told me that we should ask them for support and they will investigate.

OK, the Ubuntu pipeline succeeded, so the migration is OK.

We'll have to keep an eye to see if we will have empty/non-started pipelines again

enabled an automatic merge when the pipeline for 9cda8ca8 succeeds

canceled the automatic merge

merged

mentioned in commit 9c8700f2

added Continuos Integration label