fa7523d3aa ci: Extend docs (MarcoFalke)
fa493ef088 ci: Make ci system read-only on the git work tree (MarcoFalke)
fab1333292 ci: Remove git from required packages on host (MarcoFalke)
fa00393bce ci: Make all filesystem operations inside docker (MarcoFalke)
Pull request description:
Running the ci completely in a docker, without leaving any traces on the host system is not possible right now because the ccache and depends dir needs to be propagated back and picked up by the host for caching.
Fixes#17372
ACKs for top commit:
JeremyRubin:
tested ACK fa7523d3aa
Tree-SHA512: 4bce1a0f883bcbdb34abf409bdbc80d420c5da2045d2f9c5536ac433f9e5b490f23df084546c8c049f688b487572bbfc4f9c4029e9e672f4d9279739d066ed2e