Remove scrollbar from video tag strip and add bounce animation

Hidden scrollbars for `.video-tag-strip--scroll` in CSS to improve aesthetics.
Implemented a "peek" (bounce) animation in `HashtagStripHelper` that triggers when the tag list is rendered and overflows the container, indicating to the user that the list is scrollable.
Added unit tests for the new logic.

css/tailwind.source.css

@@ -2424,27 +2424,14 @@
     overflow-y: hidden;
     -webkit-overflow-scrolling: touch;
     padding-bottom: var(--space-xs);
-    scrollbar-width: thin;
-    scrollbar-color: var(--scrollbar-thumb) transparent;
+    scrollbar-width: none;
+    -ms-overflow-style: none;
   }
 
   .video-tag-strip--scroll::-webkit-scrollbar {
-    height: 4px;
-  }
-
-  .video-tag-strip--scroll::-webkit-scrollbar-track {
-    background:
-      linear-gradient(
-        to bottom,
-        transparent calc(50% - 0.5px),
-        var(--scrollbar-track) calc(50% - 0.5px) calc(50% + 0.5px),
-        transparent calc(50% + 0.5px)
-      );
-  }
-
-  .video-tag-strip--scroll::-webkit-scrollbar-thumb {
-    background: var(--scrollbar-thumb);
-    border-radius: var(--radius-pill);
+    display: none;
+    width: 0;
+    height: 0;
   }
 
   .video-tag-pill {