Update ARIA11 to address issue #1308 (#2339)

Adds text for ARIA 1.2 form role.

Closes #1308

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Co-authored-by: Mike Gower <[email protected]>

Author: fstrr

techniques/aria/ARIA11.html

@@ -20,7 +20,7 @@ <h1>Using ARIA landmarks to identify regions of a page</h1>
 </p>
       <p>Landmarks also can help sighted keyboard-only users navigate to sections of a page using a <a href="https://www.tpgi.com/improving-access-to-landmark-navigation/">browser plugin</a>. 
 </p>
-      <p>Landmarks are inserted into the page using the role attribute on an element that marks the section. The value of the attribute is the name of the landmark. These role values are listed below:</p>
+      <p>Landmarks are inserted into the page using the role attribute on an element that marks the section. The value of the attribute is the name of the landmark. These role values are listed below. For HTML mappings of landmark roles, refer to the <cite>Rules of ARIA attribute usage by HTML element</cite> table in the <a href="https://www.w3.org/TR/html-aria/">ARIA In HTML recommendation</a>.</p>
       <ul>
          <li><code class="language-html">banner</code>: A region that contains the prime heading or internal title of a page.</li>
          <li><code class="language-html">navigation</code>: A region that contains navigation links links to other pages or different parts of the same page.</li>