win: Fix GYP build of http_transport_test_server
win: Fix GYP build of http_transport_test_server

The C++ http_transport_test_server was added in 439ba730c5ae and the
missing GYP build description was corrected in 0e144fb9aeff, but this
wasn’t complete for Windows. ws2_32.lib was missing.

Bug: crashpad:227
Change-Id: I2a0810468f857a02ad1a997c569eee6d9c05c7da
Reviewed-on: https://chromium-review.googlesource.com/1167210
Reviewed-by: Joshua Peraza <f5809a5e35ec7e1bd0e25cb0a0b68bb433cf6f17@chromium.org>
Commit-Queue: Mark Mentovai <f1b5a91d4d6ad523f2610114591c007e75d15084@chromium.org>

chromium/crashpad,chromium/crashpad,chromium/crashpad