Custom JS text area in customizer is being formatted wrong in document

@sam-skirrow just posting here what we did to fix this…

WordPress 4.1 requires us to use a sanitize_callback filter when creating settings for the customizer (with good reason).
Since you’re using the kirki framework to create these customizer settings, kirki detects that this is a textarea field and so it automatically applies the esc_textarea filter.

However, you can override this callback and use your own when declaring the field, so all that we needed to do in order to fix this was add a js sanitization calback there instead of the esc_textarea.