Only remove whitespace from end of text node

[knabar]

Given an element like

<p>
    <b>A</b> B
</p>

the current code would remove the space before B.

This PR fixes the issue by only removing whitespace from the end of any text node.

[rwestergren]

Had this same issue and was getting ready to push up a similar fix.

[litvinov-an]

Given an element like

<p>
    <b>A</b> B
</p>

the current code would remove the space before B.

This PR fixes the issue by only removing whitespace from the end of any text node.

The proposed solution helped me