Update rules for flat config

[gracepark]

Closes: #589

This now updates the rules as ESLint has updated the rules API for custom rules: https://eslint.org/blog/2023/09/preparing-custom-rules-eslint-v9/

Tested and looks like it's now working as expected:

/workspaces/eslint-plugin-github/test-examples/flat/src/forEachTest.js
  1:1  error  Filename 'forEachTest.js' does not match the regex naming convention  github/filenames-match-regex

/workspaces/eslint-plugin-github/test-examples/flat/src/getAttribute.js
  13:3   error  event.preventDefault() inside an async function is error prone                  github/async-preventdefault
  21:4   error  "scroll" event listener is not cancellable and so `passive: true` does nothing  github/no-useless-passive
  30:16  error  event.currentTarget inside an async function is error prone                     github/async-currenttarget

[Copilot]

Copilot reviewed 5 out of 6 changed files in this pull request and generated 1 comment.

Files not reviewed (1)

• lib/rules/async-currenttarget.js: Evaluated as low risk

Tip: Turn on automatic Copilot reviews for this repository to get quick feedback on every pull request. Learn more

[Copilot]

event.currentTarget might be null after the await call. Add a null check before accessing getAttribute.

Suggested change

	const text = event.currentTarget.getAttribute('data-text')
	if (event.currentTarget === null) return;
	const text = event.currentTarget.getAttribute('data-text')