py3: fix generated non-ascii message in test-notify.t
The resulting "Subject:" header contains an encoded word in Python 3 so
we have to add distinct outputs for Python 3 but underlying values are
the same:
>>> from email.header import decode_header
>>> decode_header('=?utf-8?b?w6AuLi4=?=')
[(b'\xc3\xa0...', 'utf-8')]
[tool.black]
line-length = 80
exclude = '''
build/
| wheelhouse/
| dist/
| packages/
| \.hg/
| \.mypy_cache/
| \.venv/
| mercurial/thirdparty/
| hgext/fsmonitor/pywatchman/
| contrib/python-zstandard/
| contrib/grey.py
'''
skip-string-normalization = true
quiet = true