WIP: invalid indentation for multiline <Form::Element> (failing test)

[jelhan]

This adds a failing test that indentation is invalid (accordingly to default template linting) if <Form::Element> uses multiple lines for it's arguments and attributes on input:

Taking this input:

<form.element
  @property="foo">
  @placeholder="foo">
/>

I would expect an output, which passes template linting. An example would be:

<form.element
  @property="foo"
  as |el|
>
  <el.control placeholder="foo" />
</form.element>

But I see this one as demonstrated by failing test:

<form.element
  @property="foo"
as |el|><el.control placeholder="foo" /></form.element>

Template linter throws errors due to indentation of </form.element> and <el.control />.

[simonihmig]

Confirmed. But I believe there is not much we can do about it. Related: ember-template-lint/ember-template-recast#82