Fix need for refresh for `.js§ config changes

[Mouvedia]

What steps are needed to reproduce the bug?

a { opacity: 0.5 }

1. choose js in the config tab

module.exports = {
  "rules": {
    "alpha-value-notation": ["percentage"]
  }
}

module.exports = {
  "rules": {
    "alpha-value-notation": ["percentage", {
      "exceptProperties": "opacity"
    }]
  }
}

What did you expect to happen?

To not have to refresh the page.

What actually happened?

The error remains if I don't refresh the page.