Fix unicode error on copying over extracted files from zip. (#3874)
Fix unicode error on copying over extracted files from zip. (#3874)

Fix unicode error on copying over extracted files from zip.

Refs #3579

The problem here is that under very hard unit-testable/reproducable
circumstances a zip-file with unicode filenames get's extracted to a
temporary directory and while calling `copy_over` which calls
`shutil.copytree` which fails on our production systems with a
UnicodeDecodeError.

Reproducing this is something along the lines of

>>> shutil.copytree(u'/tmp/tmp8WG6A8/', u'/tmp/tmp8WG6A8-2/')
# doesn't error...
>>> shutil.copytree('/tmp/tmp8WG6A8/', u'/tmp/tmp8WG6A8-2/')
UnicodeDecodeError: 'ascii' codec can't decode 	byte 0xd0 in ...

Checking all relevant environment configs in our production systems, all
LANG, LC_ALL and related configs are perfectly fine. It's not related to
uwsgi, it's not related to EFS so it's something else I have absolutely
no idea about :-/

kumar303/addons-server,tsl143/addons-server,mstriemer/olympia,mozilla/olympia,mstriemer/addons-server,Revanth47/addons-server,mozilla/olympia,mozilla/olympia,diox/olympia,mstriemer/addons-server,lavish205/olympia,atiqueahmedziad/addons-server,harry-7/addons-server,aviarypl/mozilla-l10n-addons-server,harikishen/addons-server,kumar303/olympia,kumar303/olympia,bqbn/addons-server,aviarypl/mozilla-l10n-addons-server,psiinon/addons-server,mstriemer/olympia,atiqueahmedziad/addons-server,Revanth47/addons-server,mstriemer/addons-server,aviarypl/mozilla-l10n-addons-server,diox/olympia,atiqueahmedziad/addons-server,mstriemer/olympia,harikishen/addons-server,mstriemer/addons-server,eviljeff/olympia,mozilla/addons-server,eviljeff/olympia,tsl143/addons-server,mozilla/addons-server,kumar303/addons-server,aviarypl/mozilla-l10n-addons-server,mozilla/olympia,diox/olympia,harikishen/addons-server,harikishen/addons-server,lavish205/olympia,wagnerand/olympia,lavish205/olympia,lavish205/olympia,wagnerand/olympia,bqbn/addons-server,wagnerand/addons-server,wagnerand/olympia,Revanth47/addons-server,wagnerand/addons-server,eviljeff/olympia,wagnerand/addons-server,bqbn/addons-server,harry-7/addons-server,mozilla/addons-server,wagnerand/addons-server,wagnerand/olympia,tsl143/addons-server,psiinon/addons-server,kumar303/addons-server,bqbn/addons-server,Revanth47/addons-server,psiinon/addons-server,atiqueahmedziad/addons-server,harry-7/addons-server,eviljeff/olympia,kumar303/olympia,tsl143/addons-server,kumar303/addons-server,mstriemer/olympia,mozilla/addons-server,harry-7/addons-server,diox/olympia,kumar303/olympia,psiinon/addons-server