Display column headers of feature flag table on small screen

app/views/projects/feature_flags/_table.html.haml

@@ -7,6 +7,8 @@
 
     .gl-responsive-table-row{ role: 'row' }
       .table-section.section-10{ role: 'gridcell' }
+        .table-mobile-header{ role: "rowheader" }= s_('FeatureFlags|Status')
+        .table-mobile-content
           - if feature_flag.active?
             %span.badge.badge-success
               = s_('FeatureFlags|Active')
@@ -14,7 +16,9 @@
             %span.badge.badge-danger
               = s_('FeatureFlags|Inactive')
 
-      .table-section.section-50.d-flex.flex-column{ role: 'gridcell' }
+      .table-section.section-50{ role: 'gridcell' }
+        .table-mobile-header{ role: "rowheader" }= s_('FeatureFlags|Feature Flag')
+        .table-mobile-content.d-flex.flex-column
           .text-monospace= feature_flag.name
           .text-secondary= feature_flag.description