Duplicacy does not read the environment variable

Bug
#1

Please describe what you are doing to trigger the bug:

OS: Ubuntu 16.04.5 LTS (GNU/Linux 3.13.0-57-generic x86_64)
App: duplicacy 2.1.2 (2e5cbc)

~$ export DUPLICACY_PASSWORD='foo' DUPLICACY_B2_ID=bar DUPLICACY_B2_KEY=baz
~$ duplicacy backup

Please describe what you expect to happen (but doesn’t):

I expect the backup to proceed without asking me for credentials.

Please describe what actually happens (the wrong behaviour):

It asks for the credentials:

~$ duplicacy backup
Repository set to /home/noah
Storage set to b2://noah
Enter Backblaze Account ID:
#2

Is your repository name (grep \"name\" .duplicacy/preferences) “default” or some custom name? In the latter case you would need to add that name after DUPLICACY_ in the environment variable name.