test-copies: add a `p` branch similar to the `a` but on the new files
This branch will be used to create merge case that mirror ones involving the `a` branch.
Differential Revision: https://phab.mercurial-scm.org/D10055
[tool.black]
line-length = 80
exclude = '''
build/
| wheelhouse/
| dist/
| packages/
| \.hg/
| \.mypy_cache/
| \.venv/
| mercurial/thirdparty/
'''
skip-string-normalization = true
quiet = true