pyoxidizer: formatting bazel definitions
This meets the Bazel style guide:
https://docs.bazel.build/versions/master/skylark/bzl-style.html
and was mostly done automatically with buildifier.
Differential Revision: https://phab.mercurial-scm.org/D8521
[tool.black]
line-length = 80
exclude = '''
build/
| wheelhouse/
| dist/
| packages/
| \.hg/
| \.mypy_cache/
| \.venv/
| mercurial/thirdparty/
'''
skip-string-normalization = true
quiet = true