Upgrades for 4.10: Linux, Electrum, Debian Buster 10.5, firmware

Closes #17841, #17828, #17790, #17834, and #15952

See merge request tails/tails!123

Use Transifex _release branches instead of _completed ones

Closes #16774

See merge request tails/tails!113

Remove broken Thunderbird protocol selection

Closes #17276

See merge request tails/tails!111

Hide Thunderbird welcome message

See merge request tails/tails!114

Fix building Vagrant box on Debian testing/sid

Closes #17872

See merge request tails/tails!122

Right now this is a no-op as the exact same versions are in testing and sid.
But Electrum updates in sid tend to break stuff (e.g. #17828) on Buster,
so let's at least avoid RC bugs from breaking Tails.

According to
tails/tails#17461 (comment 151109), "Upcoming version of Electrum (4.0) requires python-trezor 0.12. This version of python-trezor is also required for the newest Trezor firmware update!"

Folks on #17461 are reporting WIP about having python3-trezor in
buster-backports, so let's hope this is temporary, because the risk
python3-trezor/sid becomes uninstallable on Buster is too high for my taste.
Still, in the meantime, let's avoid breaking TREZOR support in Tails 4.10.

refs #17461

Otherwise this command fails because "Daemon not running",
and thus we abort our wrapper script and Electrum won't start.

refs #17828

Otherwise, Electrum aborts on startup with an exception:

    ValueError: Non keyword-only attributes are not allowed after
    a keyword-only attribute.

I've reported to Debian the fact this dependency should be versioned:
https://bugs.debian.org/968563

refs #17828

I've mentioned this upstream on https://bugs.debian.org/968563,
without filing a proper bug report as I did not test on sid.

refs #17828

On a fast system, I've seen the "I clone the Git repository […]" scenario fail
because "test -d '/home/amnesia/testing/.git" returned 1. This check was done
just a few milliseconds after "Unpacking objects: 100%" appeared in the
Terminal. My hypothesis here is that Git takes a a little bit of time, after
displaying "Unpacking objects: 100%", until it actually puts the cloned files
into place.

Upgrade Tor to 0.4.3.6

Closes #17835

See merge request tails/tails!115

Initially I had set this to 2.3 (Stretch), because most of the code we're
analyzing is meant to be run on our Jenkins isobuilders or isotesters, that
currently run Stretch.

But Rubocop 0.81+ don't support analyzing code targeted at Ruby 2.3,
so let's bump this to 2.5 (Buster), so that at least Rubocop can run.
Rubocop 0.88.0 detects 58 offenses, but that'll be for another day.

I've seen the "Use GNOME Disks to unlock a USB drive that has a basic VeraCrypt
volume with a keyfile" scenario fail with "cannot find
GnomeDisksUnlockDialogKeyfileComboBox.png on the screen (FindFailed)".

The video shows that the previous steps happened super quickly via Dogtail,
while the dialog box was not fully rendered on screen yet, so I understand the
keyfiles combo box was not visible yet when we tried to click on it. Let's wait
a bit for it to appear.

Note that this can go away in Tails 5.0, which will have GNOME Disks ≥ 3.35.2,
which fixes #15952 ⇒ we can use Dogtail for interacting with the keyfiles
combo box too.

These drivers, when loaded during the "SquashFS file order" part of the release
process, reflect the hardware being used at the time, which:

 - won't match the broad range of hardware our users use
 - unnecessarily leaks information about the RM's hardware

So let's not include them in the SquashFS sort file.

Electrum 4.x depends on:

 - a version of python3-ecdsa that's neither in Buster nor
   in buster-backports, so let's install it from sid
 - a version of python3-protobuf that's not in Buster,
   so let's install it from buster-backports

refs #17828

We'll need to install python3-protobuf from there.

refs #17828

refs #17841, #17834

This upgrades to Buster 10.5 and makes a newer kernel available.

refs #17841, #17790

Merge remote-tracking branch 'origin/feature/17835-upgrade-tor-0.4.6+force-all-tests' into feature/17841-17828-17790-17835-upgrades-for-4.10+force-all-tests

pigz, i.e. "Parallel Implementation of GZip", takes advantage of multiple
processors and multiple cores when compressing data.

Recent vagrant-libvirt's create_box.sh uses pigz if it's available, which
speeds up the creation of our Vagrant build box on multi-core machines.

refs #17872

It's not included in vagrant-libvirt 0.1.2-1 anymore.

refs #17872

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Translation: Tails/wiki/src/news/zwiebelfreunde_raided.*.po
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Translation: Tails/wiki/src/news/version_4.9.*.po
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Translation: Tails/wiki/src/news/version_4.9.*.po
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Translation: Tails/wiki/src/news/version_4.9.*.po
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Translation: Tails/wiki/src/news/version_4.9.*.po
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Translation: Tails/wiki/src/news/version_4.9.*.po
Translate-URL: http://translate.tails.boum.org/projects/tails/wikisrcnewsversion_49po/pt/