docs: fix overflow on static bottom app bar demos

Author: hperrin

packages/site/src/routes/demo/bottom-app-bar/_Fab.svelte

@@ -120,6 +120,7 @@
   }
 
   .flexor {
+    overflow: hidden;
     display: inline-flex;
     flex-direction: column;
   }

packages/site/src/routes/demo/bottom-app-bar/_Static.svelte

@@ -103,6 +103,7 @@
   }
 
   .flexor {
+    overflow: hidden;
     display: inline-flex;
     flex-direction: column;
   }