Created tests for RestaurantService, fixed a few mistakes

Api/Controllers/RestaurantController.cs

BusinessLayer.Tests/BusinessLayer.Tests.csproj

BusinessLayer.Tests/Services/RestaurantServiceTests.cs

BusinessLayer/DTOs/Restaurant/RestaurantDetailDto.cs

BusinessLayer/DTOs/ReviewAggregate/ReviewAggregateDTO.cs

...essLayer/Services/RestaurantService/IRestaurantService.cs

...nessLayer/Services/RestaurantService/RestaurantService.cs

DAL/Data/RestaurantDBContext.cs

TestUtilities/FakeData/FakeDataInitializer.cs

TestUtilities/Mocks/MockedDbContext.cs

TestUtilities/TestUtilities.csproj

pv179-project.sln