[ban-types] support banning []

[papb]

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have read the FAQ and my problem is not listed.

Repro

{
  "rules": {
    "@typescript-eslint/ban-types": [
      "error",
      {
        "extendDefaults": true,
        "types": {
          "[]": "Don't use the empty array type `[]`, it will only allow empty arrays. Use `SomeType[]` instead.",
          "[[]]": "Don't use `[[]]`, it would only allow an array with a single element which is an empty array. Use `SomeType[][]` instead.",
          "[[[]]]": "Don't use `[[[]]]`. Use `SomeType[][][]` instead."
        }
      }
    ]
  }
}

type X = [];

// tsconfig.json
{
	"compilerOptions": {
		"module": "commonjs",
		"strict": true,
		"target": "es2017",
		"outDir": "./dist",
	}
}

Expected Result

The custom ban to work

Actual Result

No errors

Additional Info

None

Versions

package	version
@typescript-eslint/eslint-plugin	3.10.1
@typescript-eslint/parser	3.10.1
TypeScript	4.0.2
ESLint	7.9.0
node	12.18.0