refactor(lang): remove runeToUpper wrapper and use unicode.ToUpper directly

The runeToUpper() function was a simple wrapper around unicode.ToUpper()
with only one call site. Removed the wrapper to simplify the code and
call unicode.ToUpper() directly in splitCamel().

Author: karrybit

lang/util.go

@@ -27,17 +27,13 @@ func runeIsUpper(r rune) bool {
 	return r >= 'A' && r <= 'Z'
 }
 
-func runeToUpper(r rune) rune {
-	return unicode.ToUpper(r)
-}
-
 func splitCamel(text string) string {
 	var builder strings.Builder
 	var previousRune rune
 	var wordLength int
 	for i, r := range text {
 		if i == 0 {
-			previousRune = runeToUpper(r)
+			previousRune = unicode.ToUpper(r)
 			continue
 		}