test: use a python script in `test-transaction-rollback-on-sigpipe.t`
This still does not work on Windows, but at least this is a python script now.
Differential Revision: https://phab.mercurial-scm.org/D10947
# See http://EditorConfig.org for the specification
root = true
[*.py]
indent_size = 4
indent_style = space
trim_trailing_whitespace = true
end_of_line = lf
[*.{c,h}]
indent_size = 8
indent_style = tab
trim_trailing_whitespace = true
end_of_line = lf
[*.t]
indent_size = 2
indent_style = space
trim_trailing_whitespace = false
end_of_line = lf