Xpra: Ticket #2002: allow wasapi gstreamer elements

Was disabled before because they were either not included in the binary installations of gstreamer or they just didn't work.

Newer versions seem to work, though there are some issues: Bug 797329 - Live Audio Playback from Microphone Goes Silent on Windows wasapi.

Wed, 24 Oct 2018 04:06:44 GMT - Antoine Martin: status changed; resolution set

Done in r20801.

Sat, 23 Jan 2021 05:39:30 GMT - migration script:

this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/2002