Delete useless check

tcr-roman-numerals/src/main/java/fr/ippon/kata/numeral/Numerals.java

@@ -3,10 +3,6 @@ package fr.ippon.kata.numeral;
 public class Numerals {
 
   public static String toRoman(int arabic) {
-    if (arabic == 0) {
-      return "";
-    }
-
     return "I".repeat(arabic);
   }
 }