fix: also await for settled in case there's no fork but there's async work

[paoloricciuti]

@PatrickG correctly pointed out that we don't fork every time (for example, we don't do it when the user press the back button) so we have to include settled in the promises to await concurrently.

@PatrickG was also suggesting to always fork if available but I feel that would add more overhead.

WDYT?

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[PatrickG]

I made a little demo to see that always forking is probably better than using settled.
Clicking "show slow stuff" and then navigating to /other takes 10 seconds while only navigating to /other takes 1 second.
nvm, I tricked myself. It only took 10 seconds because in webcontainers we queue requests (which was my idea) :D
I changed somethingSlow() to a normal function and now navigating to /other always takes 1 second. So I guess using settled is fine.

[paoloricciuti]

I made a little demo to see that always forking is probably better than using settled. Clicking "show slow stuff" and then navigating to /other takes 10 seconds while only navigating to /other takes 1 second.

Created #14822 as an alternative...it seems better, I wonder if it could lead to some nasty race conditions tho...let's see

[PatrickG]

I made a little demo to see that always forking is probably better than using settled. Clicking "show slow stuff" and then navigating to /other takes 10 seconds while only navigating to /other takes 1 second.

Created #14822 as an alternative...it seems better, I wonder if it could lead to some nasty race conditions tho...let's see

I didn't see your response. See my edited comment.

[paoloricciuti]

Oh lol...then nevermind I guess

[Rich-Harris]

closing in favour of #14829