Remove unused internal or unexported functions (#3481)

internal/action/infocomplete.go

@@ -135,15 +135,6 @@ headerLoop:
 	return chosen, suggestions
 }
 
-func contains(s []string, e string) bool {
-	for _, a := range s {
-		if a == e {
-			return true
-		}
-	}
-	return false
-}
-
 // OptionComplete autocompletes options
 func OptionComplete(b *buffer.Buffer) ([]string, []string) {
 	c := b.GetActiveCursor()