Do not allow to change the sysinfo in demo mode

src/settings.js

@@ -498,6 +498,8 @@ function setSysinfoConfig(sysinfoConfig, callback) {
     assert.strictEqual(typeof sysinfoConfig, 'object');
     assert.strictEqual(typeof callback, 'function');
 
+    if (isDemo()) return callback(new BoxError(BoxError.BAD_FIELD, 'Not allowed in demo mode'));
+
     sysinfo.testConfig(sysinfoConfig, function (error) {
         if (error) return callback(error);