in CachingProxyTests/src/CachingProxyTest.cs [241:245]
public async Task Retry_After_500()
{
myRealTestServer.Conditional500SendErrorOnce = true;
await AssertGetResponse("/real/conditional-500.txt", HttpStatusCode.OK, (message, bytes) => AssertStatusHeader(message, CachingProxyStatus.MISS));
}