Undefined name 'autotune_directory' in oref0-autotune.py

[cclauss]

The variable autotune_directory must be defined before it can be used. Discovered via #1189

$ flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics
./bin/oref0-autotune.py:113:28: F821 undefined name 'autotune_directory'
    with open(os.path.join(autotune_directory, 'nightscout.profile.json'), 'w') as f:
                           ^
1     F821 undefined name 'autotune_directory'
1

[scottleibrand]

Have you done, or are you planning to do a PR to fix?

[cclauss]

I was unsure how to fix this so I opened an issue that the fix would be clearer for someone else.

[danamlewis]

Addressed in #1196.