Remove use of redundant String.substring() parameter.

Author: garydgregory

src/main/java/org/apache/commons/cli/Util.java

@@ -38,11 +38,11 @@ static String stripLeadingHyphens(final String str)
         }
         if (str.startsWith("--"))
         {
-            return str.substring(2, str.length());
+            return str.substring(2);
         }
         else if (str.startsWith("-"))
         {
-            return str.substring(1, str.length());
+            return str.substring(1);
         }
 
         return str;