(rollup) preventAssignment: true (#400)

Author: MatthijsBurgh

build/rollup.config.js

@@ -31,8 +31,11 @@ const baseConfig = {
       }),
     ],
     replace: {
-      'process.env.NODE_ENV': JSON.stringify('production'),
-      'process.env.ES_BUILD': JSON.stringify('false'),
+      preventAssignment: true,
+      values: {
+        'process.env.NODE_ENV': JSON.stringify('production'),
+        'process.env.ES_BUILD': JSON.stringify('false'),
+      },
     },
     vue: {
       css: true,