[eslint-config] Support Eslint 9

[marcoreni]

Summary

Eslint 8 is going EOL on October 5. Rushstack eslint packages do not support Eslint 9.

Inside the "Eslint v9 support" issue of Eslint (eslint/eslint#18391 ) rushstack is mentioned but only regarding the eslint-patch package. eslint-plugin and eslint-plugin-security packages are not tracked and they stick to eslint v8 in peerDeps.

Repro steps

Expected result:

Actual result:

Details

Standard questions

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Question	Answer
@rushstack/eslint-config version?
Operating system?
Would you consider contributing a PR?
TypeScript compiler version?
Node.js version (node -v)?

[mrose]

I would love to use eslint-config in my latest project but can't since we're using Eslint V9

[Bwvolleyball]

Supposedly this works with ESLint 9, but it's not working with an eslint.config.mjs file. Any ideas?