arti: Elide the -c help in the expected output of the CLI tests.

The help output of the -c option includes some local paths, which can be quite long on some platforms, spanning over multiple lines. This causes the CLI tests to fail, because they expect each of the paths from the -c help to fit on a single line.

To fix this, we can use trycmd's ... to match as many lines as needed.

Closes #1509 (closed)