Copy some documentation files only on Tor Browser

We do not need to copy the changelogs for Base Browser and Privacy Browser, at least for now, since they are used only in about:tbupdate, which is Tor Browser-only.

We should exclude from Base Browser also

Libevent.txt
PluggableTransports/*
Torbutton.txt
Tor-Launcher.txt
Tor.txt

In addition to that, we should copy, only for Privacy Browser, some copyright notice for uBlock Origin.

Edited Feb 09, 2023 by Pier Angelo Vendrame

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