MINOR: Fix load config properties may get error in windows due to file seperate (#813)

diff --git a/eventmesh-connector-plugin/eventmesh-connector-rocketmq/src/main/java/org/apache/eventmesh/connector/rocketmq/config/ConfigurationWrapper.java b/eventmesh-connector-plugin/eventmesh-connector-rocketmq/src/main/java/org/apache/eventmesh/connector/rocketmq/config/ConfigurationWrapper.java
index a2ec1d1..83036bb 100644
--- a/eventmesh-connector-plugin/eventmesh-connector-rocketmq/src/main/java/org/apache/eventmesh/connector/rocketmq/config/ConfigurationWrapper.java
+++ b/eventmesh-connector-plugin/eventmesh-connector-rocketmq/src/main/java/org/apache/eventmesh/connector/rocketmq/config/ConfigurationWrapper.java
@@ -52,7 +52,7 @@
      */
     private void loadProperties() {
         try (InputStream resourceAsStream = ConfigurationWrapper.class.getResourceAsStream(
-            File.separator + EventMeshConstants.EVENTMESH_CONF_FILE)) {
+            "/" + EventMeshConstants.EVENTMESH_CONF_FILE)) {
             if (resourceAsStream != null) {
                 properties.load(resourceAsStream);
             }