in CachingProxyTests/src/CachingProxyTest.cs [500:509]
private async Task AssertHeadResponse(string url, HttpStatusCode expectedCode,
Action<HttpResponseMessage> assertions)
{
myOutput.WriteLine("*** HEAD " + url);
using var response = await myServer.CreateClient().SendAsync(
new HttpRequestMessage(HttpMethod.Head, url), HttpCompletionOption.ResponseContentRead);
myOutput.WriteLine(response.ToString());
Assert.Equal(expectedCode, response.StatusCode);
assertions(response);
}