Added missing env key for "scheduler.driver"

Author: x7airworker

src/main/java/org/javawebstack/framework/config/Config.java

@@ -28,6 +28,7 @@ public Config() {
             put("HTTP_SERVER_JSON", "http.server.json");
             put("HTTP_SERVER_TMP", "http.server.tmp");
             put("CRYPT_KEY", "crypt.key");
+            put("SCHEDULER_DRIVER", "scheduler.driver");
         }});
     }