Erdtree does not reset terminal state when no matches are found

[AdamNiederer]

To reproduce:

$ erd --version
3.0.2
$ erd --pattern apatternthatdoesnotexist /
No entries to show with given arguments.
$ <the cursor is now invisible>

This problem can be reproduced on both urxvt and kitty, and can be worked around by running tput cnorm afterwards