MessageList tests added.

Author: abdurrahmanekr

src/MessageList/__tests__/MessageList.js

@@ -10,4 +10,4 @@ describe('MessageList component', () => {
     expect(component.length).toBe(1);
     expect(toJson(component)).toMatchSnapshot();
   });
-});
+});

src/MessageList/__tests__/__snapshots__/MessageList.js.snap

@@ -3,5 +3,10 @@
 exports[`MessageList component should render without issues 1`] = `
 <div
   className="rce-container-mlist"
-/>
+>
+  <div
+    className="rce-mlist"
+    onScroll={[Function]}
+  />
+</div>
 `;