AnacondaWebUIWorkflow breaks terminal output

[velezd]

AnacondaWebUIWorkflow is using virt-install command to start VM and to get console output. But virsh console switches the terminal in to raw mode and that breaks output of the whole pipeline. New lines do not return to the start.

This is not an issue if the output is redirected in to a file, eg. running in jenkins or GitHub CI.
And it can be workaround-ed but running Permian with /dev/null on stdin ./pipeline ... < /dev/null (Permian will create new pty).

[pholica]

This could be also resolved by introducing a singleton for "dummy" (input-less) PTY that could be created by https://python.readthedocs.io/en/stable/library/pty.html#pty.openpty as it's currently done in

permian/libpermian/cli/__init__.py

Line 35 in b5c2e3c

_, pty_slave = pty.openpty()

(which could be eventually also removed).
This singleton slave pty could be then used in situations where some commands need to manipulate with pty but it's not needed to provide any input. And having one shared should also not have any negative impact on number of file descriptors.