Update ecmaVersion to 2021

[fisker]

No description provided.

[fisker]

This requires #815

[sindresorhus]

There are some more places to update:

eslint-plugin-unicorn/index.js
13:				ecmaVersion: 2020,

eslint-plugin-unicorn/test/prefer-starts-ends-with.js
8:		ecmaVersion: 2020

eslint-plugin-unicorn/test/better-regex.js
7:		ecmaVersion: 2020

eslint-plugin-unicorn/test/prefer-node-remove.js
15:		ecmaVersion: 2020

eslint-plugin-unicorn/test/prefer-node-append.js
9:		ecmaVersion: 2020

eslint-plugin-unicorn/test/prefer-optional-catch-binding.js
11:		ecmaVersion: 2020

eslint-plugin-unicorn/test/no-for-loop.js
8:		ecmaVersion: 2020
14:		ecmaVersion: 5

eslint-plugin-unicorn/test/new-for-builtins.js
8:		ecmaVersion: 2020,

eslint-plugin-unicorn/test/no-null.js
12:		ecmaVersion: 2020,

eslint-plugin-unicorn/test/number-literal-case.js
11:		ecmaVersion: 2020

eslint-plugin-unicorn/test/no-fn-reference-in-iterator.js
27:		ecmaVersion: 2020

eslint-plugin-unicorn/test/prefer-spread.js
8:		ecmaVersion: 2020

eslint-plugin-unicorn/test/no-keyword-prefix.js
7:		ecmaVersion: 2020,
220:			parserOptions: {ecmaVersion: 6},
225:			parserOptions: {ecmaVersion: 6},

eslint-plugin-unicorn/test/no-reduce.js
13:		ecmaVersion: 2020

eslint-plugin-unicorn/test/import-style.js
10:		ecmaVersion: 2020
588:		ecmaVersion: 2020

eslint-plugin-unicorn/test/no-console-spaces.js
8:		ecmaVersion: 2020

eslint-plugin-unicorn/test/no-useless-undefined.js
11:		ecmaVersion: 2020
245:		ecmaVersion: 2020

eslint-plugin-unicorn/test/no-process-exit.js
8:		ecmaVersion: 2020,

eslint-plugin-unicorn/test/prefer-set-has.js
10:		ecmaVersion: 2020,

eslint-plugin-unicorn/test/prefer-array-find.js
17:		ecmaVersion: 2020,

eslint-plugin-unicorn/test/no-object-as-default-parameter.js
9:		ecmaVersion: 2020
175:		ecmaVersion: 2020

eslint-plugin-unicorn/test/prevent-abbreviations.js
14:		ecmaVersion: 5
23:		ecmaVersion: 2020,

eslint-plugin-unicorn/test/integration/config.js
14:		ecmaVersion: 2020,

eslint-plugin-unicorn/test/consistent-function-scoping.js
10:		ecmaVersion: 2020,
655:		ecmaVersion: 2020,

eslint-plugin-unicorn/test/throw-new-error.js
9:		ecmaVersion: 2020

eslint-plugin-unicorn/test/prefer-number-properties.js
32:		ecmaVersion: 2020

eslint-plugin-unicorn/test/catch-error-name.js
10:		ecmaVersion: 2020

[fisker]

I think they don't have to use the latest?

[sindresorhus]

Maybe not always, but it's sometimes hard to see when it could have been useful. And it's annoying to have to individually judge every time it updates. Wouldn't it be easier if everything was the same? We could maybe define a shared constants and import it into every test. Or better yet, some kind of custom test helper, like #554

[fisker]

I'll work on #554 when I have time.

[fisker]

typescript-eslint/typescript-eslint#2468