fix newline characters in comment

[Varorbc]

No description provided.

[Rob-Hague]

Thanks! are you able to modify one of the .ppk files in test/Data in order to demonstrate the problem and fix?

[Varorbc]

The current test case has this problem because it is a ppk file obtained from an embedded resource, so it works fine. This problem occurs if you read directly from disk. So how do I add test cases? I hope you can give me some advice.

[scott-xu]

@Varorbc Just out of curiosity, what's the binary difference between embedded resource and loose file?

[Varorbc]

@scott-xu Sorry about that, I got the issue mixed up earlier. Let me correct it: The PPK files in the current test cases use \n for new lines, but the PPK files generated by the older PuTTYgen client use \r\n.

[Rob-Hague]

right, because the comment is included in the MAC, so we don't want to greedily match the \r. Thanks!

FYI: the changed .ppk file still has LF line endings because we normalize these files:

SSH.NET/.gitattributes

Line 21 in 3b4f2cf

test/Data/*eol=lf

but the problem is understood well enough