Fix unnecessary whitespace stripping on liquid html attribute break

[charlespwd]

Fixes #99

Input:

It should not consider the trailing whitespace of the last attribute to be sensitive
printWidth: 1
<ul {% render 'hi', arg: 1 %}></ul>
<img {% render 'hi', arg: 1 %}>
<self-closing {% render 'hi', arg: 1 %}/>

Output:

It should not consider the trailing whitespace of the last attribute to be sensitive
printWidth: 1
<ul
  {% render 'hi',
    arg: 1
  %}
></ul>
<img
  {% render 'hi',
    arg: 1
  %}
>
<self-closing
  {% render 'hi',
    arg: 1
  %}
/>