Update our documentation to OpenPGP Applet in Debian

We should replace occurrences of “Tails OpenPGP Applet” by “OpenPGP Applet”, maybe this will do (untested and probably not enough):

git grep -l 'Tails OpenPGP Applet' | while read file ; do sed -i 's/Tails OpenPGP Applet/OpenPGP Applet/' $file ; done

Feature Branch: doc/11244-openpgp-applet-in-debian

Parent Task: #10190 (closed)

Original created by @sajolida on 11244 (Redmine)