add private fields

refactor test

rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/transform/TbJsonPathNode.java

@@ -49,10 +49,10 @@ import java.util.concurrent.ExecutionException;
 )
 public class TbJsonPathNode implements TbNode {
 
-    TbJsonPathNodeConfiguration config;
+    private TbJsonPathNodeConfiguration config;
-    Configuration configurationJsonPath;
+    private Configuration configurationJsonPath;
-    JsonPath jsonPath;
+    private JsonPath jsonPath;
-    String jsonPathValue;
+    private String jsonPathValue;
 
     @Override
     public void init(TbContext ctx, TbNodeConfiguration configuration) throws TbNodeException {

rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/transform/TbJsonPathNodeTest.java

@@ -71,11 +71,6 @@ public class TbJsonPathNodeTest {
         node.destroy();
     }
 
-    @Test
-    void givenDefaultConfig_whenInit_thenOK() {
-        assertThat(node.config).isEqualTo(config);
-    }
-
     @Test
     void givenDefaultConfig_whenInit_thenFail() {
         config.setJsonPath("");