Description
Is your proposal related to a problem?
In Formatting Code Automatically the example uses a command-line option to configure prettier to favor single quotes. At the end it directs people to how they might configure their editor. But the editor is going to use prettier defaults, not the command with options that's part of the git hook, so the editor will keep changing to double quotes, making git diff less useful, until changes are committed and it switches back to single quotes.
Describe the solution you'd like
Plan A would be not to include any configuration in the example. This would be most concise and simple. Full disclosure this is partly because I'm personally on a "don't customize anything" kick wanting to just take the defaults on everything wherever possible.
Describe alternatives you've considered
If there's objection to removing the single-quote configuration from the example, plan B would be to add a "prettier" key to the package.json customization in the example. That way the prettier config would be where all integrations could find it.