PLT-6651 - Overlay issue modal (#6473)

* PLT-6651 - Overlay issue modal

* Fixing mentions badge

webapp/sass/components/_mentions.scss

@@ -9,7 +9,7 @@
     z-index: 10;
 }
 
-.mention-badge {
+.badge {
     background-color: #777;
     border-radius: 10px;
     color: #fff;

webapp/sass/components/_modal.scss

@@ -76,6 +76,12 @@
         color: alpha-color($black, .9);
         width: 100%;
 
+        .modal--overflow {
+            .modal-body {
+                overflow: visible;
+            }
+        }
+
         &.modal-image {
             .modal-backdrop {
                 &.in {