twig-block-line-breaks rule on top level in file

[MalteJanz]

Currently there is no empty line suggestion between twig blocks on the top level.

Example:

{% block first %}
    first 
{% endblock %}
{% block second %}
    second
{% endblock %}

Should be formatted like:

{% block first %}
    first 
{% endblock %}

{% block second %}
    second
{% endblock %}

This is already the case lower in the syntax tree (not top level in the file)