Fix 64 Basic token parser to not add new line if current basic progra…

…m is empty.

src/libraries/Highbyte.DotNet6502.Systems.Commodore64/Utils/C64BasicTokenParser.cs

@@ -108,7 +108,7 @@ public string GetBasicText(byte[] basicPrg, bool spaceAfterLineNumber = true, bo
                 break;
         }
 
-        if (addNewLineAfterLastCharacter)
+        if (sb.Length > 0 && addNewLineAfterLastCharacter)
             sb.AppendLine();
 
         return sb.ToString();