Fix issue in padding newlines before keywords rule

[nunofgs]

When using ES6 syntax, the "requirePaddingNewlinesBeforeKeywords" rule fails when exporting a function. For example:

export function create() {
   …
}

Will return the error:

Keyword `function` should have an empty line above it:
    89 | */
    90 |
    91 |export function create() {
--------------^

However, if the export keyword is removed, the rule works.