public async Task AddRoleToUsers()
        {
            // Arrange
            var userId = 3;

            var roleId = context
                         .Roles
                         .Where(r => r.RoleLevel == RoleLevel.ADMIN)
                         .Select(r => r.Id)
                         .FirstOrDefault();

            // Act
            var result = await sut.AddRole(userId, roleId);

            // Assert
            Assert.That(result.Success, Is.True);
        }