修改优秀案例时间

src/views/menu/rehearsalTask/learning.vue

@@ -76,7 +76,7 @@
             </div>
             <div class="mainItem" @click="goInfo(item.id)">
               <div>演练时间</div>
-              <div>{{ item.drillTime }}</div>
+              <div v-if="item.drillStartTime">{{ item.drillStartTime }}-{{ item.drillEndTime }}</div>
             </div>
             
           </div>