Fix Debian Emacs Ispell

After using the testing repo for Debian Buster to install Emacs 27 I ran into an issue where spellcheck through ispell would not work

debian-ispell-set-startup-menu: Symbol's value as variable is void: ispell-menu-map-needed

Turns out the issue was in dictionaries-common, and fixed ages ago. Debian doesn’t like to keep with the times though, so I had to also install dictionaries-common from the testing repo to finally fix the issue!

sudo apt --target-release=testing install dictionaries-common

😎

Starting new Ispell process ispell with default dictionary...done
Checking spelling of THIS...
THIS is correct