Doc: fix blockquote mismatch (#41295)

* fix: blockquote mismatch in card

Refs: #41292

* fix: blockquote mismatch in reboot

Refs: #41292

Author: viniciusvts

Diff for: site/content/docs/5.3/components/card.md

@@ -173,10 +173,14 @@ Card headers can be styled by adding `.card-header` to `<h*>` elements.
     Quote
   </div>
   <div class="card-body">
-    <blockquote class="blockquote mb-0">
-      <p>A well-known quote, contained in a blockquote element.</p>
-      <footer class="blockquote-footer">Someone famous in <cite title="Source Title">Source Title</cite></footer>
-    </blockquote>
+    <figure>
+      <blockquote class="blockquote">
+        <p>A well-known quote, contained in a blockquote element.</p>
+      </blockquote>
+      <figcaption class="blockquote-footer">
+        Someone famous in <cite title="Source Title">Source Title</cite>
+      </figcaption>
+    </figure>
   </div>
 </div>
 {{< /example >}}

Diff for: site/content/docs/5.3/content/reboot.md

@@ -428,10 +428,14 @@ The `<address>` element is updated to reset the browser default `font-style` fro
 The default `margin` on blockquotes is `1em 40px`, so we reset that to `0 0 1rem` for something more consistent with other elements.
 
 <div class="bd-example">
-  <blockquote class="blockquote">
-    <p>A well-known quote, contained in a blockquote element.</p>
-  </blockquote>
-  <p>Someone famous in <cite title="Source Title">Source Title</cite></p>
+  <figure>
+    <blockquote class="blockquote">
+      <p>A well-known quote, contained in a blockquote element.</p>
+    </blockquote>
+    <figcaption>
+      Someone famous in <cite title="Source Title">Source Title</cite>
+    </figcaption>
+  </figure>
 </div>
 
 ### Inline elements