RHEL-9 doesn't ship flake8. Note that it was already disabled for
%check anyway, but we also have an internal beaker test that runs
test.sh where we would have to disable it too, at which point it's just
easier to do that in test.sh itself.
While at it, remove all traces of flake8 from the spec file as well, to
avoid confusion in the future.
Related: #1929210
Previously, PyEnchant raised a DictNotFoundError from the SpellChecker
constructor in case it didn't find the given language. This was
recently[1] changed/fixed upstream to actually handle that error in the
constructor and then raise a DefaultLanguageNotFoundError instead.
Adapt our code to it but also keep handling the previous error, just in
case.
Note that this was never fixed in rpmlint upstream since that has moved
on and rewritten quite a bit of the codebase, fixing this traceback in
the process, hence a downstream-only patch here.
[1] commit 5fc8ecc458b7b84d88ce629f74905549790141ee at:
https://github.com/pyenchant/pyenchant/Resolves: #1929210
