Don't communicate with docker until necessary

[guilhem]

Currently, docker plugin communicate with docker at each run, even if not necessary. When using socket activation, it spawns docker daemon + all networks, and it has impact on battery consumption.

Postponing docker communication will prevent it.

Another way can be to separate Dockerfile linting plugin from Docker management, itself. User being able to disable Docker communication without losing linting.

[bwateratmsft]

This would probably be solved by #3263. Right now our initial communications with Docker are to get the context so we can set up Dockerode; if the CLI alone was used then none of that would be needed, and I think all features could become truly demand-based.

[bwateratmsft]

I added this issue to the list on #3263.

[guilhem]

thanks @bwateratmsft, I subscribed.

[bwateratmsft]

Fixed by #3586

[bwateratmsft]

This has now been released in Docker extension version 1.23.0.