fails to create .config directory

[Jelmer Vernooij]

From https://bugs.debian.org/944379:

breezy doesn't always create it's config dir resulting in an exception.
The current behaviour breaks ros-wstool since the switch from bzr to brz:

https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/ros-wstool.html

Steps to reproduce:

$ cd $(mktemp -d)
$ HOME=$(pwd) brz init
Created a standalone tree (format: 2a)
$ touch foo
$ HOME=$(pwd) brz status
brz: ERROR: [Errno 2] No such file or directory: '/tmp/tmp.7OnfYj98A5/.config/breezy'

Excrept from the .bzr.log:

0.039 encoding stdout as sys.stdout encoding 'UTF-8'
0.039 encoding stdout as sys.stdout encoding 'UTF-8'
0.039 encoding stdout as sys.stdout encoding 'UTF-8'
0.049 breezy version: 3.0.1
0.049 brz arguments: ['status']
0.154 encoding stdout as sys.stdout encoding 'UTF-8'
0.170 opening working tree '/tmp/tmp.7OnfYj98A5'
0.172 check paths: None
0.173 creating config directory: '/tmp/tmp.7OnfYj98A5/.config/breezy'
0.173 Transferred: 0kB (0.0kB/s r:0kB w:0kB)
0.175 Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/breezy/ignores.py", line 93, in get_user_ignores
    f = open(path, 'rb')
FileNotFoundError: [Errno 2] No such file or directory: '/tmp/tmp.7OnfYj98A5/.config/breezy/ignore'