On blend enter, only pass -it to podman if stdout is tty

[dancojocaru2000]

I was trying to move a file out of a container onto the host OS by using tar:

tar.arch -chC /usr/share/icons/hicolor/16x16/apps file.png | tar -x

This failed, with tar.arch printing tar: Refusing to write archive contents to terminal (missing -f option?), because, even if I piped the output of tar.arch, blend enter called podman with -it, giving the tar inside the arch container a TTY, and so tar refused to print the output.

blend enter should check if stdout is a tty and only pass -it if true.

There should also be flags to force the behaviour one way or the other.