[Usage Collection] Small performance improvements

[afharo]

Summary

This PR replaces 2 usages of array.reduce((acc, [key, value]} => ({...acc, [key]: value}), {}) in favour of Object.fromEntries(array.map(([key, value]) => [key, value])). The performance is much better on the second option, while still maintaining the declarative & non-mutating approach: https://measurethat.net/Benchmarks/Show/11657/0/arrayreduce-vs-objectfromentries-arraymap

NOTE: If these changes look good, I can create an issue to follow up on catching similar usages.

Q: Should we create an eslint rule to somehow recommend the latter?
A: We shouldn't. If we add the mutation-based alternatives, there are many ways to approach this, and different browsers report different performance results. Running https://jsben.ch/UJguY in Safari vs. Chrome vs. Firefox shows that Chrome has a boosted .reduce + mutation of the acc value implementation:

From left to right: Safari, Chrome, Firefox.

Checklist

Delete any items that are not applicable to this PR.

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• Any UI touched in this PR is usable by keyboard only (learn more about keyboard accessibility)
• Any UI touched in this PR does not create any new axe failures (run axe in browser: FF, Chrome)
• If a plugin configuration key changed, check if it needs to be allowlisted in the cloud and added to the docker list
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser)
• This was checked for cross-browser compatibility

For maintainers

• This was checked for breaking API changes and was labeled appropriately

[Bamieh]

I feel these are micro-optimizations. I'd rather we'd not put time on.

1. perf tests are rarely representative of real case scenarios
2. As a web application there are a lot of bottlenecks (network, threads comminucation, etc). Even if we make the loops and other transformation operations literally take 0ms it will not add provide any speed improvements.

As for readabilty they are both equally readable to me so i have no preference.

[afharo]

@elasticmachine merge upstream

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 4f2ed13

Metrics [docs]

✅ unchanged

History

• 💚 Build #106814 succeeded f48a56c
• 💔 Build #106797 failed c8b1def
• 💔 Build #106772 failed 34fa438

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@elasticmachine merge upstream