Make "Correct!" optional in random_praise()

[gadenbuie]

learnr/R/praise.R

Lines 64 to 66 in 7eb2b29

	random_praise <- function() {
	paste0("Correct! ", sample(random_praises, 1))
	}

The Correct! prefix is hardcoded. Removing it or making it optional would let other packages more easily drop random_praise() into their messages.

[gadenbuie]

We're leaning toward removing the "Correct! " for consistency with random_encouragement() and to give authors more flexibility to include random praise in other places in feedback messages.