Adding getProperty to export the ListenerRSS properties + related tests

tests/index-spec.ts

@@ -195,6 +195,16 @@ describe("test class RSS: jsonfile", function () {
     });
   });
 
+  describe("export property", function () {
+    it("should export properties into a ListenerRSSInfos", function () {
+      // given
+      const myListener = new Listeners(infosListener);
+
+      // assertions
+      expect(myListener.getProperty()).to.be.eql(infosListener);
+    });
+  });
+
   describe("data fetching", function () {
     it("fetches without issues", async function () {
       // given