Fix issue boards sidebar alignment and sidebar toggle spec

app/assets/stylesheets/pages/boards.scss

@@ -298,12 +298,8 @@
 .issue-boards-sidebar {
   &.right-sidebar {
-    top: 153px;
+    top: 0;
     bottom: 0;
-
-    @media (min-width: $screen-sm-min) {
-      top: 220px;
-    }
   }
   .issuable-sidebar-header {

spec/features/boards/sidebar_spec.rb

@@ -54,7 +54,7 @@ describe 'Issue Boards', feature: true, js: true do
     expect(page).to have_selector('.issue-boards-sidebar')
-    find('.gutter-toggle').click
+    find('.gutter-toggle').trigger('click')
     expect(page).not_to have_selector('.issue-boards-sidebar')
   end