Bug Description

When exporting to HTML file, all callouts are ignored.

How to Reproduce

Create a document with this content (here formatted as markdown)

The following is a callout:
> 📌
> CALLOUT 1

And this is a quote:
> QUOTE 2
And that's all we need.

Click "Share > Export As > HTML"

The resulting html file will contain exactly this content (formatted for readability):

<p>The following is a callout:</p>
<p>And this is a quote:</p>
<blockquote>QUOTE 2</blockquote>
<p>And that's all we need.</p>
<br>

I.e. the callout part is gone without a trace, while the quote is preserved.
I just thought it'd be good to know that quotes are not affected, in case that makes analysis easier.

Expected Behavior

The entire document should be exported.

Operating System

Linux (debian unstable)

AppFlowy Version(s)

0.7.1 (.deb package)

Screenshots

No response

Additional Context

No response