Fix test_asciisignalio to work on Windows

[zm711]

Since Windows use a different newline in order for the csv to work the newline argument must be specified. Adding this doesn't affect Linux testing, but it makes my life better when running local tests on Windows.

[pep8speaks]

Hello @zm711! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2023-10-20 21:27:44 UTC

[apdavison]

For future reference, the reason for this is given in the Python docs here: https://docs.python.org/3/library/csv.html#id3

[zm711]

Thanks @apdavison, next time I'll include the link documentation in the PR message itself.