* Goal is to enable caching of dependency builds to speed up CI build
times significantly
* Should ease transition to new plugin build template version
Always building with the Release configuration caused issues (e.g.
linking) when attempting to build non-release configurations when using
the CI build scripts.
This is not done for OpenCV as it does not support all build types.
Based on OBS plugin template build scripts with some minor adjustments:
* Adjust format check scripts to exclude ./deps folder
* Adjust release scripts to only draft releases
* Always build installers
* Always upload build artefacts
* Build opencv for Mac and Windows releases
