add buttons to click icons

src/server/views/layout-growi/widget/liker-and-seenusers.html

@@ -1,10 +1,16 @@
 <div class="liker-and-seenusers">
-  <img class="rounded-circle picture picture-sm" src="/images/icons/pagelist.svg">
-  <img class="rounded-circle picture picture-sm" src="/images/icons/timeline.svg">
-  <img class="rounded-circle picture picture-sm" src="/images/icons/recent-changes.svg">
-  <img class="rounded-circle picture picture-sm" src="/images/icons/attachment.svg">
-
-  <img class="rounded-circle picture picture-sm" src="/images/icons/user.svg">
+    <button type="button" class="bg-transparent border-0">
+      <img class="rounded-circle picture" src="/images/icons/pagelist.svg">
+    </button>
+    <button type="button" class="bg-transparent border-0">
+      <img class="rounded-circle picture" src="/images/icons/timeline.svg">
+    </button>
+    <button type="button" class="bg-transparent border-0">
+      <img class="rounded-circle picture" src="/images/icons/recent-changes.svg">
+    </button>
+    <button type="button" class="bg-transparent border-0">
+      <img class="rounded-circle picture" src="/images/icons/attachment.svg">
+    </button>
 
   <!-- <div
     id="liker-list"