Using shortcut Key for underline applies the style in the editor but fails to save Underlining Text

[theodrak]

Lexxy Fails to handle underlining of text
v 0.7.3.beta

Steps to reproduce

1. Highlight Text - Cmd + U to underline the text.
   (This applies the Underline class to the element in the editor)
   <span class="lexxy-content__underline" data-lexical-text="true">Text to Underline</span>

2. Save Changes

3. Refresh
   Html as displayed on the underlined text after saving
   <p dir="auto"><span data-lexical-text="true">Text to Underline</span></p>

output html in page

<p><b><strong>Bold Test</strong></b> Text to Underline</p>

The text is no longer underlined. (Lexxy loses the notion that it was underlined)