fix: windows crashes & builds (#55)

- Doing jobs in parallels in GHA (Divide build time by 3).
- Now use custom webrtc builds for this repo
- Windows crashes when receiving video is now fixed (thanks @cloudwebrtc)
    - Now reading defines from webrtc.ninja
- Added a small create_pc test to be sure libwebrtc is working/linked correctly 
- Fix MacOS builds 
- Fixed Linux duplicated main build error (due to nasm)

webrtc-sys/libwebrtc/.gitignore

@@ -2,7 +2,9 @@
 src
 .gclient_*
 depot_tools
+ninja
 
 # builds
-macos
-linux
+win*
+macos*
+linux*