bug#46033: up arrow in query replace should not step into the prompt

[reporter]

Up/down arrow is useful in the replace prompt, because sometimes
the replace text is long and spans multiple lines, so up/down is
handy to navigate it.

Up arrow can also retrieve previous history lines when you are
already at the top line of the replacement.

However, if there is a multiline replacement default in the
prompt then up arrow steps into the prompt first and only further
presses retrieve history:

https://i.imgur.com/7G3FcPX.png

Up arrow should not lead the user uselessly into the prompt text.