1 second is a bit excessive. Use 200ms which should cover most quick
folder changes.
Add an option to make that delay configurable by the users.
References: https://todo.sr.ht/~rjarry/aerc/16
Fixes: cb3090956c ("dirlist: skip unnecessary change-folder action")
Suggested-by: Koni Marti <koni.marti@gmail.com>
Signed-off-by: Robin Jarry <robin@jarry.cc>