Remove unused ToPascalCase

Author: jakubfijalkowski

src/Tools/LeanCode.ContractsGenerator/Extensions/StringExtensions.cs

@@ -6,10 +6,5 @@ public static string ToCamelCase(this string str)
         {
             return char.ToLowerInvariant(str[0]) + str[1..];
         }
-
-        public static string ToPascalCase(this string str)
-        {
-            return char.ToUpperInvariant(str[0]) + str[1..];
-        }
     }
 }