fix: add the build date/time and the epoch to the plugin.json

Change-Id: I6c6d59aba2380c71cfd00df120702b26a3e2c6b8

Author: mtlljm

.config/webpack/webpack.config.ts

@@ -180,7 +180,7 @@ const config = async (env): Promise<Configuration> => ({
           },
           {
             search: /\%buildTime\%/g,
-            replace: Date.now(),
+            replace: Date.now().toString(),
           },
         ],
       },