fix display of media items position in group panel

stylesheets/_session_group_panel.scss

@@ -78,7 +78,8 @@
   }
 
   .module-attachment-section__items {
-    justify-content: space-evenly;
+    display: grid;
+    grid-template-columns: repeat(3, 1fr);
   }
 
   .module-media {
@@ -116,11 +117,11 @@
         .module-media-grid-item {
           height: calc(
             22vw / 3.5
-          ); //.group-settings is 22vw and we want threee rows with some space so divide it by 3.5
+          ); //.group-settings is 22vw and we want three rows with some space so divide it by 3.5
           width: calc(
             22vw / 3.5
-          ); //.group-settings is 22vw and we want threee rows with some space so divide it by 3.5
+          ); //.group-settings is 22vw and we want three rows with some space so divide it by 3.5
-          margin-right: 0;
+          margin: auto;
         }
       }
     }