[BUG] Finding items on the help screen doesn't work #644

Describe the bug
Finding items on the help screen (F1) doesn't work properly.

To Reproduce
Steps to reproduce the behavior:

1. Go to help screen.
2. Attempt to use "Find item forward" or "Find item backward"
3. See error

Expected behavior
Scrolling of a help page to next/previous result when "."/"," pressed.

Desktop (please complete the following information):

• OS: Linux Mint 22.2 Cinnamon
• Terminal: zsh
• Version: ncmpcpp 0.9.2

Additional context
Searching for items on the playlist screen works fine.