chore: speed up CI a bit (hopefully)

[gtm-nayan]

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[Rich-Harris]

is this ready? what's the tl;dr on what it's actually doing?

[benmccann]

As I recall, I had several points of feedback that weren't addressed yet. I don't know if @gtm-nayan still wants to continue with this or not? If not, perhaps we can split the flakiness fixes out into a new PR and close this one as I'm not sure we want to merge everything that was in this one though my memory of it could be outdated

[benmccann]

I removed some of the parts I was less sure of to unblock this and get the rest in. Feel free to resend those parts in a new PR with some more explanation