Issue #3239838 by longwave, Spokje, nod_, xjm: Update core eslint configuration to remove unused React and JSX rules

Issue #2981652 by ApacheEx, corbacho, drpal, dawehner, xjm, alexpott, lauriii: Format core JavaScript using recently add Prettier

Issue #2978964 by ApacheEx, drpal, lauriii, corbacho, samuel.mortenson, tedbow, alexpott, droplet: Use Prettier for formatting core JavaScript

Issue #2925064 by drpal, dawehner, droplet, xjm, webchick, justafish: [1/2] JS codestyle: no-restricted-syntax

Revert "Issue #2925064 by drpal, dawehner, xjm, justafish, droplet: [1/2] JS codestyle: no-restricted-syntax"

This reverts commit b0a4d7e0.

Issue #2925064 by drpal, dawehner, xjm, justafish, droplet: [1/2] JS codestyle: no-restricted-syntax

This reverts commit 169e8671.