CI is too slow #508
Description
Currently CI takes about 1h-1h15mn, that's too much:
- Most of the time is obviously spent building mc-rtc with various compilers/build type
- All compilations are done from scratch
- Packaging rebuilds everything that was essentially already built during the build checks
I think we should look into:
- enabling some dependency caching (https://docs.github.com/en/actions/reference/workflows-and-actions/dependency-caching).
- using and keeping ccache output during build
- using ccache for building debian packages
In a devcontainer with a pre-polutated ccache, on my machine a full build of the default superbuild takes ~5-7mn, with most of that time actually spent on the rviz panel (we really should look into that).