Fix HTML markup

Author: garydgregory

src/main/javadoc/overview.html

@@ -585,7 +585,7 @@ <h1>Deprecating Options</h1>
           </p>
           <p>
               The examples below will implement <code>doSomething</code> in the following code block.
-          </p>p>
+          </p>
               <pre><code>
   public static void main(String[] args) {
       Option n = Option.builder("n")