Make command for replacing newlines with literals \n in SSHOperatorconnection MacOs/Linux compatible

[geovalexis]

The command line used for replacing newlines with literal \n was not working for MacOS. The problem was that the regex is prepared to match newlines of Windows type but not for Unix-type newlines (without carriage return:\r). By adding a ?("zero or one occurrence" quantifier) in between the \r and \n, we match not only Windows but also MacOS/Unix newlines.

In summary:

• On Windows, newlines are \r\n (carriage return + newline).
• On Linux/MacOS, newlines are just \n (no \r).
• \r?\n ensures that both types are matched and replaced correctly.

This command has been tested in both MacOS (Sequoia) and Windows 11 (using WSL2 > Ubuntu 22.04)

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[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.