public static CustomerDBContext GetCustomerDBContext(string dbName)
        {
            // Create options for DbContext instance
            var options = new DbContextOptionsBuilder <CustomerDBContext>()
                          .UseInMemoryDatabase(databaseName: dbName)
                          .Options;

            // Create instance of DbContext
            var dbContext = new CustomerDBContext(options);

            // Add entities in memory
            dbContext.Seed();

            return(dbContext);
        }