winhttp/tests: Fix test failures.

[Marvin]

Hi,

While running your changed tests on Windows, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?
Full results can be found at
https://testbot.winehq.org/JobDetails.pl?Key=21484

Your paranoid android.


=== w864 (32 bit winhttp) ===
winhttp.c:1030: Test failed: failed to send request 2148074273
winhttp.c:1034: Test failed: failed to retrieve certificate context 12019
winhttp.c:1039: Test failed: failed to retrieve key bitness 4317
winhttp.c:1043: Test failed: failed to retrieve certificate info 12019
winhttp.c:1056: Test failed: failed to receive response 12019
winhttp.c:1060: Test failed: failed to query available data 12019
winhttp.c:1061: Test failed: available_size = 0
winhttp.c:1066: Test failed: failed unexpectedly 12019
winhttp.c:1067: Test failed: request failed unexpectedly 3735928559
winhttp.c:1078: Test failed: WinHttpReadData failed: 12019.