Markdown tests fail on windows due to line ending different from unix one

[luigi-asprino]

This relates to #266
DOS line ending is \r\n while Unix is \n

https://www.cs.toronto.edu/~krueger/csc209h/tut/line-endings.html#:~:text=Text%20files%20created%20on%20DOS,(%22%5Cn%22).

Therefore, the expected graph contains \r\n as line-ending and the graph generated on windows has just \n.

[luigi-asprino]

On my mac (and on the remote repository I suppose) the input files of the tests contain only line feed characters (\n).
But, after pulling the files on windows, the line ending becomes \r\n.
Therefore, I thought that there must be something in git to control how the line endings are handled.
I found that this can be controlled via .gitattributes file https://docs.github.com/en/get-started/getting-started-with-git/configuring-git-to-handle-line-endings
With f555808 I added a .gitattributes file which forces (I hope) the files of the repository to be pulled with \n as line ending character.

[luigi-asprino]

I cloned the repository from scratch on windows.
I re-run the tests in the markdown module which seem to be working.
I'm going to close the issue.