Update 11.5.8 mar URLs to point to archive.tpo (tor-browser-build#41233)

We're been keeping 11.5.8 mar files on cdn.torproject.org as a watershed update for a while. We're switching to archive.tpo URLs to be able to remove it from cdn.tpo.

tor-browser-build#41233 (closed)

I've updated the xml files using this command:

sed -i -e 's|https://cdn.torproject.org/aus1/torbrowser/11.5.8/|https://archive.torproject.org/tor-package-archive/torbrowser/11.5.8/|g' *.xml

I've tried downloading a few URLs from the updated xml files and got files matching the expected sha512sum.