Fixed video size

Signed-off-by: Andre Wanlin <awanlin@spotify.com>

microsite/blog/2024-03-27-backstagecon-kubecon-24.mdx

@@ -12,30 +12,13 @@ authorImageURL: https://avatars.githubusercontent.com/u/67169551?v=4
 
 ## Celebrating Four Years of Backstage
 
-<div
-  style={{
-    position: 'relative',
-    overflow: 'hidden',
-    width: '100%',
-    paddingTop: '56.25%',
-  }}
->
-  <iframe
-    style={{
-      position: 'absolute',
-      top: 0,
-      left: 0,
-      right: 0,
-      bottom: 0,
-      width: '100%',
-      height: '100%',
-    }}
-    src="https://www.youtube.com/embed/NgYrweEbFNE"
-    frameBorder="0"
-    allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture"
-    allowFullScreen
-  ></iframe>
-</div>
+<iframe
+  src="https://www.youtube.com/embed/NgYrweEbFNE"
+  width="100%"
+  height="440"
+  allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture"
+  allowFullScreen
+></iframe>
 
 Wow! Has it already been four years since we open sourced Backstage? What an amazing run it's been so far. We continue to see the rate of pull requests steadily increase, the attendance and number of [special interest groups](https://github.com/backstage/community/tree/main/sigs) (SIGs) has grown, and more people are dedicating their time to new [project areas](https://github.com/backstage/community/tree/main/project-areas)!