Remove "blueish" correction

It's not a typo, or a correction that really needs to be made, as both
"blueish" and "bluish" are acceptable forms:
https://english.stackexchange.com/questions/18824/why-are-blueish-and-bluish-both-considered-correct-spellings

Closes: #3509
Fixes: fbb964ff ("Add several spelling corrections")