ci: enable yarn install cache

[armano2]

Motivation

https://github.com/actions/cache/blob/main/examples.md#node---yarn
https://github.com/actions/cache/blob/main/examples.md#node---yarn-2

ci build time is now reduced per job by 30s~1min

Have you read the Contributing Guidelines on pull requests?

yes

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[github-actions]

⚡️ Lighthouse report for the changes in this PR:

Category	Score
🟠 Performance	88
🟢 Accessibility	96
🟢 Best practices	100
🟢 SEO	100
🟢 PWA	95

Lighthouse ran on https://deploy-preview-4486--docusaurus-2.netlify.app/

[slorber]

Hey, that's a cool idea

Was just wondering if there isn't a way to remove all that verbosity?

I've used this action recently and it worked great, can it be used instead?
https://github.com/bahmutov/npm-install

[armano2]

it can, and its your call if you think that's a good idea

[slorber]

yes I think - uses: bahmutov/npm-install@v1 would be better.

Do you want to edit this PR or we close and I do another one?

[armano2]

i'm going to update this pr, do you think that we should apply this for windows machines to?

[slorber]

thanks, that looks fine

[slorber]

I think we can enable this on Windows too, do you see any reason not to?

[armano2]

generally caching on windows gh actions seem to be slow, i will try it out

[slorber]

didn't know that, is it documented or your personal experience? slower than no caching at all?

[slorber]

let's merge this for now and see if we can improve windows in another PR