Resync .gitlab-ci.yml and .gitignore following Yarn 4 in 11.x

While we are here we should also add .yarn to core/.gitignore because Yarn 4 uses it and ignores it, then you switch to a Yarn 1 branch and remnants are left behind.

Ran into cherry-pick conflicts on 📌 Merge the build and lint stages in core MR pipelines Downport , added an MR here.

catch → changed the visibility of the branch 3428614-resync-.gitlab-ci.yml-and to hidden.

The Needs Review Queue Bot → tested this issue. It fails the Drupal core commit checks. Therefore, this issue status is now "Needs work".

This does not mean that the patch necessarily needs to be re-rolled or the MR rebased. Read the Issue Summary, the issue tags and the latest discussion here to determine what needs to be done.

Consult the Drupal Contributor Guide → to find step-by-step guides for working with issues.

Changing the branch to hopefully increase the bot happiness.

Seems like it did the trick

nod_ → closed merge request !8950

Committed and pushed c559ce6491 to 10.4.x and 8b2a6cacf2 to 10.3.x. Thanks!

can be improved to make cherry pick possible

nod_ → reopened merge request !8950

so we can't cherry pick directly but git can figure out the conflicts by itself now

nod_ → closed merge request !8950

patch still looking good after sleeping a bit on it

Automatically closed - issue fixed for 2 weeks with no activity.