Disable failing 15 thumbernails full-stack test on windows
Disable failing 15 thumbernails full-stack test on windows

BUG=webrtc:7301

Review-Url: https://codereview.webrtc.org/2737703005
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#17105}

ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc