Git Missing from Boot2Qt Docker-based Toolchain

When working with a project that came from DS

fetch content will not work because git is not included in the Boot2Qt docker-based QBSP.

I can manually add it by editing the dockerfile and rebuilding the image, but I think we should automatically include it in our docker-based QBSPs that we offer in the installer, especially since Design Studio is using this method to install the designer components.

We just need to add git and ca-certificates to the apt install list inside of the Dockerfile to fix this.