Update copyright year (#801)

diff --git a/NOTICE b/NOTICE
index cf58f0a..6367c40 100644
--- a/NOTICE
+++ b/NOTICE
@@ -1,5 +1,5 @@
 Apache Dubbo Admin
-Copyright 2018-2019 The Apache Software Foundation
+Copyright 2018-2021 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).
diff --git a/dubbo-admin-distribution/src/NOTICE b/dubbo-admin-distribution/src/NOTICE
index 446a88f..df92423 100644
--- a/dubbo-admin-distribution/src/NOTICE
+++ b/dubbo-admin-distribution/src/NOTICE
@@ -1,5 +1,5 @@
 Apache Dubbo Admin
-Copyright 2018-2019 The Apache Software Foundation
+Copyright 2018-2021 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).
@@ -100,7 +100,7 @@
 
 ========================================================================
 Apache Dubbo
-Copyright 2018-2019 The Apache Software Foundation
+Copyright 2018-2021 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).
diff --git a/dubbo-admin-ui/src/components/public/Footers.vue b/dubbo-admin-ui/src/components/public/Footers.vue
index 64f4e73..6ad8ae6 100644
--- a/dubbo-admin-ui/src/components/public/Footers.vue
+++ b/dubbo-admin-ui/src/components/public/Footers.vue
@@ -18,7 +18,7 @@
 <template>
   <v-footer inset height="auto" class="pa-3 footer-border-top">
     <v-spacer></v-spacer>
-    <span class="caption mr-1"><strong>Copyright</strong> &copy;2018-2019 <strong>The Apache Software Foundation.</strong></span>
+    <span class="caption mr-1"><strong>Copyright</strong> &copy;2018-2021 <strong>The Apache Software Foundation.</strong></span>
   </v-footer>
 </template>
 <script>