Updated jest function

I currenly have Jest  v27.2.5 and it does not have `mockResolveValue`, but has the same functionality method `mockResolvedValue`.

Author: topmonroe9

content/fundamentals/unit-testing.md

@@ -176,7 +176,7 @@ describe('CatsController', () => {
     })
     .useMocker((token) => {
       if (token === CatsService) {
-        return { findAll: jest.fn().mockResolveValue(results) };
+        return { findAll: jest.fn().mockResolvedValue(results) };
       }
       if (typeof token === 'function') {
         const mockMetadata = moduleMocker.getMetadata(token) as MockFunctionMetadata<any, any>;