Fix trademark-brand-policy.htm (#18)

Co-authored-by: Piotr Chmielnik <[email protected]>

_includes/footer.html

@@ -100,7 +100,7 @@ <h4>{{ column.title }}</h4>
             </div>
           </div>
           <div class="footer--legal-rows-wrapper--row">
-            &copy; OpenSearch contributors, {{ 'now' | date: "%Y" }}. OpenSearch is a <a href="/trademark-brand-policy.html">registered trademark</a> of Amazon Web Services.</a> <br /><br /> 
+            &copy; OpenSearch contributors, {{ 'now' | date: "%Y" }}. OpenSearch is a <a href="https://opensearch.org/trademark-brand-policy.html">registered trademark</a> of Amazon Web Services.</a> <br /><br /> 
             {% if page.notice == true or layout.notice == true %} OpenSearch includes certain Apache-licensed Elasticsearch code from Elasticsearch B.V. and other source code. Elasticsearch B.V. is not the source of that other source code. ELASTICSEARCH is a registered trademark of Elasticsearch B.V. <br /><br /> {% endif %}
 
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