📦 Update dependency eslint-config-prettier to v9

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
eslint-config-prettier	8.10.0 -> 9.0.0

See all other Renovate PRs on the Dependency Dashboard

How to resolve breaking changes

This PR may introduce breaking changes that require manual intervention. In such cases, you will need to check out this branch, fix the cause of the breakage, and commit the fix to ensure a green CI build. To check out and update this PR, follow the steps below:

# Check out the PR branch
git checkout -b renovate/major-linting-devdependencies main
git pull https://github.com/ampproject/amphtml.git renovate/major-linting-devdependencies

# Directly make fixes and commit them
amp lint --fix # For lint errors in JS files
amp prettify --fix # For prettier errors in non-JS files
# Edit source code in case of new compiler warnings / errors

# Push the changes to the branch
git push [email protected]:ampproject/amphtml.git renovate/major-linting-devdependencies:renovate/major-linting-devdependencies

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Release Notes

prettier/eslint-config-prettier (eslint-config-prettier)

v9.0.0

Compare Source

• Added: The CLI helper tool now works with eslint.config.js (flat config). Just like ESLint itself, the CLI tool automatically first tries eslint.config.js and then eslintrc, and you can force which one to use by setting the [ESLINT_USE_FLAT_CONFIG] environment variable. Note that the config of eslint-config-prettier has always been compatible with eslint.config.js (flat config) – it was just the CLI tool that needed updating. On top of that, the docs have been updated to mention how to use both eslint.config.js (flat config) and eslintrc, and the tests now test both config systems.
• Changed: [unicode-bom] is no longer turned off. Prettier preserves the BOM if you have one, and does not add one if missing. It was wrong of eslint-config-prettier to disable that rule. If you get ESLint errors after upgrading, either add "unicode-bom": "off" to your config to disable it again, or run ESLint with --fix to fix all files according to the rule (add or remove BOM). Thanks to Nicolas Stepien (@​nstepien)!

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Configuration

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