gstplugin: Fix for UWP build

SetThreadErrorMode() API is available on UWP but flag values
are desktop API only. Since error dialogs don't exist on UWP,
we don't need to suppress it

Part-of: <gstreamer/gstreamer!1569>
25 jobs for !1569 with uwp-build in 36 minutes and 36 seconds (queued for 3 seconds)
merge request