Improve Jest config

[maxpatiiuk]

• Look into https://dev.to/vantanev/make-your-jest-tests-up-to-20-faster-by-changing-a-single-setting-i36
• Look into tests in https://github.com/facebook/react/tree/main/packages/react/src/__tests__ and take inspiration from them
• Make use of https://testing-playground.com/ when writing UI tests
• Look into custom Jest runners
  • https://github.com/jest-community/awesome-jest#runners
  • https://jestjs.io/docs/configuration#runner-string
  • https://github.com/azz/jest-runner-tsc
• Rewrite old .js tests to .ts
• https://github.com/ballercat/jest-plugin-must-assert
• https://www.jest-preview.com/docs/examples/create-react-app/
• https://github.com/clarkbw/jest-localstorage-mock
• https://github.com/hustcc/jest-date-mock
• https://github.com/evelynhathaway/jest-location-mock