Set readline output to non-prompting on method exit

[szymonj99]

This PR sets the output to be non-prompting after the pgets method exits. This follows other examples in the codebase and seems like a sane thing to do.

Verification

• Start msfconsole
• Get a session
• Ensure calling sessions -i -1 works as expected
• Ensure you can background the session
• Ensure user input to the console in the session and Console contexts works as expected
• Ensure CI passes

[smcintyre-r7]

Does this fix some kind of a bug you ran into or are you just trying to align it with the other examples in the code base?