Add moment.js for build time tracking and update subproject reference

Author: weilycoder

package.json

@@ -26,6 +26,7 @@
     "hexo-server": "^3.0.0",
     "hexo-theme-landscape": "^1.0.0",
     "hexo-util": "^3.3.0",
-    "hexo-wordcount": "^6.0.1"
+    "hexo-wordcount": "^6.0.1",
+    "moment": "^2.30.1"
   }
 }

scripts/update_build_time.js

@@ -0,0 +1,4 @@
+hexo.extend.filter.register('before_generate', function () {
+  const moment = require('moment');
+  hexo.config.build_time = moment().format('YYYY-MM-DD HH:mm:ss');
+});