php-mf2 is parsing mf2 properties on mf1 roots

[sknebel]

(gRegorLove asked for clarification about this in https://github.com/microformats/microformats2-parsing/issues/37, but I'd agree with Kartik's reading there, and there should be a bug here tracking this)

(sample based on https://islandinthenet.com/reply/, who asked for help in #wordpress today)

<div class="hentry">
Reply to: <a class="h-cite u-in-reply-to" href="https://example.com/post">A post</a>
<div class="entry-content">
<p>This is a reply.</p>
</div>
</div>

results in a in-reply-to property on the resulting entry, despite u-in-reply-to not being a known property for mf1 hentry