bump delete-artifact action to v2 to be node 16 compatible.

[mbien]

github will switch everything to Node 16 on the 18th of May:
https://github.blog/changelog/2023-05-04-github-actions-all-actions-will-run-on-node16-instead-of-node12/

delete-artifact is the last remaining action which we haven't updated yet. We access the action via a git submodule since it is third-party. Other actions were bumped in #4770 and #5376

• this PR moves the delete-artifact submodule to the v2.0.0 tag
• bonus: updated git ignore to ignore all private folders by default

after that we shouldn't see any warnings of this kind anymore:

Cleanup Workflow Artifacts
Node.js 12 actions are deprecated. Please update the following actions to use Node.js 16: ./.github/actions/delete-artifact/. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/.

[neilcsmith-net]

We might want to run this one through delivery? There's a chance we could still be requiring testing there by that date.

[mbien]

We might want to run this one through delivery? There's a chance we could still be requiring testing there by that date.

yep. Wanted to test it on master first since delivery is broken. Will rebase if it works as expected.

edit: it worked, no action related warnings anymore, see

going to rebase and retarget to delivery

[mbien]

@neilcsmith-net done, points at delivery now

[neilcsmith-net]

Thanks! And understand about delivery being broken - makes sense - hopefully can merge the fix asap, and then get other pending PRs in.