Synchronise changes from main / 3-11-maintenance to 4-0-dev

[pirj]

Similar to https://github.com/rspec/rspec-support/pull/549

This is the result of git merge main and removal of what was mistakenly re-added during the merge, and minor fixes what became incompatible.

⚠️ I did not merge in 3-11-maintenance, but at a glance, they are on par with main.

✅ No 3.11.1 bugfix release required

This brings 4-0 closer to parity with main.

[pirj]

I was lazy to hand-pick, and I git merge'd main into this PR's branch and removed what was mistakenly re-added or fixed what became incompatible. In rspec-support, you just have 9 commits. Did you use some other method, @JonRowe ?

PS this is fine,

$ git log $(git merge-base main 4-0-dev)..main | wc -l
156

With merge, I kept all the commits, while you squashed most.

[JonRowe]

I've closed this because I prefer we don't do merges into the core branches like this, its better in my opinion to cherry-pick merge commits across (this is impossible in some cases where rebase merges have happened which is something I've been meaning to mention to you, we should always be doing merge commits or squash merges) the 4.0 situation is something I'm hoping to address in the next few weeks but if you want to cherry pick the prs across I'm happy for you to attempt that.

[JonRowe]

Equally I guess we could rebase the 4-0 changes in top of main as a "new" branch

[pirj]

Makes sense 👍