[naming-convention] Allow selecting only const variables

[nstepien]

Repro

{
  "rules": {
    "@typescript-eslint/naming-convention": [1,
      { "selector": "variable", "format": ["camelCase", "PascalCase"] },
      // { "selector": "variable", "modifiers": "const", "format": ["camelCase", "PascalCase", "UPPER_CASE"] }
    ]
  }
}

const CONSTANT_NUMBER = 1;

Expected Result
I should be able to allow UPPER_CASE for consts only.

Actual Result
I can't narrow down the variable selector.

Additional Info

Versions

package	version
@typescript-eslint/eslint-plugin	2.19.2
@typescript-eslint/parser	2.19.2
TypeScript	3.7.5
ESLint	6.8.0
node	13.8.0
npm	6.13.7

[glen-84]

Should this issue be closed? (#2291)

[nstepien]

Looks like it works, thanks! 👍