Add forum link to feedback panel (#5432) (#5441)

(cherry picked from commit b38f361)

Signed-off-by: Fanit Kolchina <kolchfa@amazon.com>
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

_includes/feedback.html

@@ -11,5 +11,6 @@
     <div class="text-small num-chars" id="num-chars">350 characters left</div>
     <button id="send" class="send-button" disabled>Send</button>
     <p class="text-small text-grey-dk-100 hidden" id="thank-you">Thank you for your feedback!</p>
+    <p class="text-small text-grey-dk-100">Have a question? <a target="_blank" href="https://forum.opensearch.org/">Ask us on the OpenSearch forum</a>.</p>
     <p class="text-small text-grey-dk-100">Want to contribute? <a class="feedback-edit" target="_blank" href="https://github.com/opensearch-project/documentation-website/edit/main/{{ page.path }}">Edit this page</a> or <a class="feedback-issue" target="_blank" href="https://github.com/opensearch-project/documentation-website/issues/new?assignees=&labels=untriaged&template=issue_template.md&title=%5BDOC%5D">create an issue</a>.</p>
 </div>

_sass/custom/custom.scss

@@ -555,8 +555,8 @@ p.label {
   list-style-type: none;
   background-color: $sidebar-color;
   padding: $sp-6 $sp-4;
-  margin-left: $sp-6;
-  margin-right: $sp-6;
+  margin-left: $sp-4;
+  margin-right: $sp-8;
   margin-bottom: 0;
   overflow: auto;
 }
@@ -571,8 +571,8 @@ p.label {
   width: calc(#{$toc-width} - 4rem);
   text-align: center;
   margin-top: 3rem;
-  margin-left: $sp-6;
-  margin-right: $sp-6;
+  margin-left: $sp-4;
+  margin-right: $sp-8;
   padding-left: 1rem;
   padding-right: 1rem;
   display: block;