Prepare release: 8.0rc2

[github-actions]

⚡ Merging this PR will automatically create a GitHub Release & publish the package ⚡

This PR was created by the Release stage 1 - create release PR (Cylc 8+ only) workflow, triggered by @datamel

Tests:

• Tests last run on master:
• ✔️ Build check passed - see the workflow run (number 9) for more info

Checklist:

• Milestone complete?
  0 other open issues/PRs on milestone cylc-8.0rc2 at time of PR creation
• Changelog up-to-date?
  • Examine pull requests made since the last release
  • "Released on" date updated? ✔️ 2022-03-23

Next steps:

• @datamel should request 1 or 2 reviews
• If any further changes are needed, push to this PR branch
• After merging, the bot will comment below with a link to the release (if not, look at the PR checks tab)

[MetRonnie]

I not sure we need this note, it perhaps suggests you won't be able to restart 8.0rc1 workflows but you can. If users jumping from a beta version to rc2 want to see what's changed, they should also read the changelog for rc1 imo

[datamel]

I added it because, due to the close timeframes of the releases, I thought users may find this useful information to have on hand if they pick up this release, skipping rc1. Happy to change the wording to pre-rc releases or remove if you feel strongly.

[datamel]

Reverted.

[MetRonnie]

(Test failures are due to MacOS runner flakiness)

[oliver-sanders]

MacOS runner flakiness

I think this is most likely caused by a genuine issue in resource release.

[github-actions]

✔️ success

Next steps for @datamel:

• view/edit the GitHub release description as appropriate
• ✔️ Milestone automatically closed

---

Comment created by workflow: Release stage 2 - auto publish, run: 20

[MetRonnie]

I think this is most likely caused by a genuine issue in resource release.

It didn't even get to the integration tests though, brew install took nearly 10 out of the 15 minutes allowed