public async Task IsManufacturerExistingByName_WithNonExistingManufacturerName_ShouldReturnFalse()
{
// Arrange
FitStoreDbContext database = this.Database;
DatabaseHelper.SeedData(database);
IManufacturerService manufacturerService = new ManufacturerService(database);
// Act
bool result = await manufacturerService.IsManufacturerExistingByName(nonExistingManufacturerName);
// Assert
result.Should().Be(false);
}