some refactoring

Author: ma-mirzaei

src/__mocks__/resizeObserverMock.ts

@@ -0,0 +1,12 @@
+// @ts-ignore
+class ResizeObserver {
+    observe() {}
+    unobserve() {}
+    disconnect() {}
+}
+
+Object.defineProperty(window, 'ResizeObserver', {
+    writable: true,
+    configurable: true,
+    value: ResizeObserver,
+});

src/setupTests.ts

@@ -3,3 +3,4 @@
 // expect(element).toHaveTextContent(/react/i)
 // learn more: https://github.com/testing-library/jest-dom
 import '@testing-library/jest-dom';
+import './__mocks__/resizeObserverMock';