Improve epub support

Warn when there are encrypted fonts in an epub file
10 jobs for master in 52 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Linting
passed #191996
linting:bandit

00:00:40

passed #191998
linting:codespell

00:00:39

passed #192002
linting:mypy

00:00:40

passed #192001
linting:pyflakes

00:00:40

failed #192000
linting:pylint

00:00:50

 
  Test
skipped #192004
tests:archlinux
skipped #192005
tests:debian
skipped #192007
tests:debian_with_bubblewrap
skipped #192009
tests:fedora
skipped #192012
tests:gentoo
 
Name Stage Failure
failed
linting:pylint Linting
$ pylint --disable=no-else-return,no-else-raise,no-else-continue,unnecessary-comprehension,raise-missing-from,unsubscriptable-object --extension-pkg-whitelist=Nautilus,GObject,Gtk,Gio,GLib,gi ./nautilus/mat2.py
************* Module mat2
nautilus/mat2.py:234:15: R1729: Use a generator instead 'any(is_valid for (is_valid, _) in map(self.__validate, files))' (use-a-generator)

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Your code has been rated at 9.93/10 (previous run: 10.00/10, -0.07)

Cleaning up file based variables
ERROR: Job failed: exit code 1