Do not change the referenced matched tag data (from gettag()).

Fixes a regression introduced in the refactor in commit
e43b7a48b08a6bbcb4e730e80395b3257681b33e

Now copy the data by value. This structure is small and no performance
regression has been seen.

This was because the tag ID was modified which made subsequent parsed tags of
this type behave strangely:

	ctx.tag->id = RSSTagGuidPermalinkTrue;

Input data to reproduce:

<rss>
<channel>

<item>
<guid isPermaLink="false">https://def/</guid>
</item>

<item>
<guid>https://abc/</guid>
</item>

</channel>
</rss>

0 files changed, 0 insertions, 0 deletions