Fixing a node config serialization test broken after adding new option 'enablePlatformVerification'

Author: barancev

java/server/test/org/openqa/grid/internal/utils/configuration/GridNodeConfigurationTest.java

@@ -180,6 +180,7 @@ public void testAsJson() {
                  + "\"register\":true,"
                  + "\"registerCycle\":5000,"
                  + "\"unregisterIfStillDownAfter\":60000,"
+                 + "\"enablePlatformVerification\":true,"
                  + "\"custom\":{},"
                  + "\"maxSession\":5,"
                  + "\"servlets\":[],"