fix(eslint-plugin): [no-unnecessary-condition] fix false positive with computed member access and branded key type

[yf-yang]

PR Checklist

• Addresses an existing open issue: fixes Bug: [@typescript-eslint/no-unnecessary-condition] False positive when enable tsconfig noUncheckedIndexedAccess and branded string key #7700
• That issue was marked as accepting prs
• Steps in Contributing were taken

Overview

TypeScript's getIndexInfoOfType only accepts pure string or number type, so instead we extract all the index infos and compare their keyType by getting the type name of the key type.

[typescript-eslint]

Thanks for the PR, @yf-yang!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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✅ Successfully ran 19 targets

• nx test eslint-plugin --coverage=false
• nx test visitor-keys --coverage=false
• nx run types:build
• nx run repo-tools:postinstall-script
• nx test parser --coverage=false
• nx test type-utils --coverage=false
• nx test typescript-estree --coverage=false
• nx test rule-schema-to-typescript-types --coverage=false
• nx test utils --coverage=false
• nx test eslint-plugin-internal --coverage=false
• nx test repo-tools --coverage=false
• nx test eslint-plugin-tslint --coverage=false
• nx test scope-manager --coverage=false
• nx run-many --target=lint --parallel
• nx run-many --target=typecheck --parallel
• nx test ast-spec --coverage=false
• nx run integration-tests:test
• nx run eslint-plugin:generate:configs
• nx run-many --target=build --parallel --exclude=website --exclude=website-eslint

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[JoshuaKGoldberg]

Looks great, thanks! Just requesting a bit more tests. 🚀

[JoshuaKGoldberg]

Btw, the Netlify failures are unrelated to this PR. You should be able to ignore them.

[yf-yang]

Just curious 👀 , you are using squash and merge option, so only the PR title should follow conventional commit guidelines, the commit messages don't matter, right?

[Josh-Cena]

so only the PR title should follow conventional commit guidelines, the commit messages don't matter, right?

That's right. You can do whatever you want with commit titles and commit as many times as you want.

[JoshuaKGoldberg]

🚀 thanks!