FEI-4957.11: Reorganize eslint configs

[kevinbarabash]

Summary:

When I initially updating the eslint config to support TypeScript, I added settings to .eslintrc.js that I should've added to eslint-config-khan/index.js. Without these settings, using @khanacademy/eslint-config in other codebases would fail.

TODO:

• update eslint-config-khan's package.json to have the appropriate peer deps

Issue: FEI-4957

Test plan:

• add some lint
• see that it's reported in VSCode
• yarn lint, see that it's reported
• fix the lint
• yarn lint, see there's no lint

[changeset-bot]

🦋 Changeset detected

Latest commit: 5b9a7b7

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@khanacademy/eslint-config	Patch

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Click here if you're a maintainer who wants to add another changeset to this PR

[khan-actions-bot]

Gerald

Required Reviewers

• @Khan/frontend-infra for changes to .eslintrc.js, .changeset/long-hairs-turn.md, packages/eslint-config-khan/README.md, packages/eslint-config-khan/index.js, packages/eslint-config-khan/package.json

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[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (main@5c50724). Click here to learn what that means.
The diff coverage is 7.69%.

❗ Current head 0072bdc differs from pull request most recent head 5b9a7b7. Consider uploading reports for the commit 5b9a7b7 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #535   +/-   ##
=======================================
  Coverage        ?   94.57%           
=======================================
  Files           ?       62           
  Lines           ?      885           
  Branches        ?      224           
=======================================
  Hits            ?      837           
  Misses          ?       48           
  Partials        ?        0           

Impacted Files	Coverage Δ
...nder-stuff-core/src/__tests__/entries.typestest.ts	0.00% <0.00%> (ø)
.../wonder-stuff-core/src/__tests__/keys.typestest.ts	0.00% <0.00%> (ø)
...onder-stuff-core/src/__tests__/values.typestest.ts	0.00% <0.00%> (ø)
packages/wonder-stuff-core/src/entries.ts	100.00% <100.00%> (ø)
packages/wonder-stuff-core/src/keys.ts	100.00% <100.00%> (ø)
packages/wonder-stuff-core/src/values.ts	100.00% <100.00%> (ø)

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[github-actions]

Size Change: 0 B

Total Size: 4.32 kB

ℹ️ View Unchanged

Filename	Size
packages/wonder-stuff-core/dist/es/index.browser.js	1.68 kB
packages/wonder-stuff-sentry/dist/es/index.browser.js	1.66 kB
packages/wonder-stuff-testing/dist/es/index.browser.js	976 B

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