* CMake: Copy PDB file to OBS build directory on Debug build
All native OBS build objects also bundle the associated PDB file for
debugging and handling crash reports.
* CMake: Add post-build commands for RelWithDebInfo
Add post-build commands for the RelWithDebInfo build config. OBS
official builds use RelWithDebInfo, so we should be able to treat it as
a release config.
* CI: Disable building OBS native plugins
Use the OBS CMake flag DISABLE_PLUGINS to disable building plugins
included with OBS (including submodule plugins like obs-browser). This
should speed up builds on Windows when we have to rebuild OBS and on
Mac.
* CI: Don't clone/update OBS submodules
The only submodules presently in OBS are in its plugins, which we don't
need to build.
* CI: Use obsproject/obs-studio instead of jp9000/obs-studio
The OBS GitHub recently changed from jp9000/obs-studio to
obsproject/obs-studio, so use that instead.
* CI: Build as RelWithDebInfo instead of Release
OBS official builds are produced with RelWithDebInfo. This will produce
a PDB file for the plugin, similar to the native OBS plugins.
* CI(Windows): Build OBS if current build config doesn't exist
If OBS libs for the current build config do not exist, build OBS before
building obs-websocket.
