Fix display logic for warning message

app/assets/javascripts/cycle_analytics/components/stage_plan_component.js.es6

@@ -13,7 +13,7 @@
       <div>
         <div class="events-description">
           {{ stage.description }}
-          <span v-if="items.length <= 50" class="pull-right">
+          <span v-if="items.length === 50" class="events-info pull-right">
             <i class="fa fa-warning has-tooltip"
               title="Limited to showing 50 events at most"
               data-placement="top"></i>

app/assets/stylesheets/pages/cycle_analytics.scss

@@ -285,12 +285,12 @@
     .events-description {
       line-height: 65px;
       padding: 0 $gl-padding;
+    }
 
-      span {
+    .events-info {
       color: $gl-text-color-secondary;
     }
   }
-  }
 
   .stage-events {
     width: 60%;