chore(docs): update usage

[danranVm]

Summary

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• Bugfix
• Feature
• Code style update
• Refactor
• Docs
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Other information:

[kefranabg]

Hi @danranVm,

Thanks for opening this PR.

This config head: [['link', { rel: 'manifest', href: '/manifest.json' }]], is not required if you want to use the PWA plugin.

However I noticed that an example of a fully PWA-compliant configuration was missing in the doc (and I think that's what you were looking for). I just opened a PR to do an update.

Closes this PR in favor of #1769