Revert "Allocate array of the correct size"

This reverts commit 60b32953a9.

Following the advices from http://shipilev.net/blog/2016/arrays-wisdom-ancients/
this seems to be faster and safer on current VMs.

src/main/java/org/apache/commons/lang3/builder/ReflectionToStringBuilder.java

@@ -346,7 +346,7 @@ public class ReflectionToStringBuilder extends ToStringBuilder {
                 list.add(e.toString());
             }
         }
-        return list.toArray(new String[list.size()]);
+        return list.toArray(ArrayUtils.EMPTY_STRING_ARRAY);
     }