public async Task GetOneSalary_ShouldReturnNull_IfNoMatch()
        {
            await dbContext.Salaries.AddAsync(new Salary { SalaryId = 1, Value = 100, TimePeriod = "some", EmployeeId = 1 });

            await dbContext.Salaries.AddAsync(new Salary { SalaryId = 2, Value = 200, TimePeriod = "some2", EmployeeId = 1 });

            await dbContext.Salaries.AddAsync(new Salary { SalaryId = 3, Value = 300, TimePeriod = "some2", EmployeeId = 2 });

            await dbContext.SaveChangesAsync();

            var dao = new PostgresDataAccessObjectService(dbContext);
            var obj = dao.GetOneSalary(11);

            Assert.Null(obj);
        }