public async Task AddingMultipleResourcesToPoolShouldMakeThemAvailable()
{
var pool = new ResourcePool <string>();
Assert.Equal(0, pool.ItemCount);
var test1 = "test1";
var test2 = "test2";
var test3 = "test3";
pool.Add(test1);
Assert.Equal(1, pool.ItemCount);
var rented1 = await pool.RentAsync();
Assert.Equal(test1, rented1);
pool.AddRange(new[] { test2, test3 });
var rented2 = await pool.RentAsync();
Assert.Equal(test2, rented2);
var rented3 = await pool.RentAsync();
Assert.Equal(test3, rented3);
}