[Draft] Update Eslint to the latest version 9 #5222
Draft
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What
Update Eslint to the latest version 9
Guides
Use the following command to convert the current eslint files to the new flat config file
npx @eslint/migrate-config .eslintrc.json
Run rushx lint to identify errors
https://eslint.org/docs/latest/use/configure/migration-guide
Known Issue
Stuk/eslint-plugin-header#57
Header/header rules no longer supported
We can look into prettier for this issue
Random CI failure related to prettier
prettier/eslint-plugin-prettier#671 (comment)
Process & policy checklist
Is this a breaking change?