[mrm-task-eslint] prettier/@typescript-eslint is no more needed.

[riywo]

When I ran mrm typescript prettier eslint, mrm added prettier/@typescript-eslint to .eslintrc.json. However, with the latest version of eslint-config-prettier, eslint won't work:

Error: Cannot read config file: /Users/riywo/riywo.com/app/node_modules/eslint-config-prettier/@typescript-eslint.js
Error: "prettier/@typescript-eslint" has been merged into "prettier" in eslint-config-prettier 8.0.0. See: https://github.com/prettier/eslint-config-prettier/blob/main/CHANGELOG.md#version-800-2021-02-21
Referenced from: /Users/riywo/riywo.com/app/.eslintrc.json

I think we can remove prettier/@typescript-eslint from here:

mrm/packages/mrm-task-eslint/index.js

Lines 121 to 128 in ca485fb

	const extensions = eslintrc.get('extends', []);
	eslintrc.merge({
	extends: [
	...(Array.isArray(extensions) ? extensions : [extensions]),
	'prettier',
	'prettier/@typescript-eslint',
	],
	});

I confirmed eslint works once I removed prettier/@typescript-eslint by hand.