[Glitch] Fix hidden overflow on interaction modal

Port 6414c28368 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/styles/components/modal.scss

@@ -1306,7 +1306,8 @@ img.modal-warning {
   width: 600px;
   background: $ui-base-color;
   border-radius: 8px;
-  overflow: hidden;
+  overflow-x: hidden;
+  overflow-y: auto;
   position: relative;
   display: block;
   padding: 20px;