Dockerfile: Remove 2 year old deprecation warning

[kpcyrd]

This finally removes support for the implicit daemon argument and unlocks full access to all subcommands.

[Stebalien]

Could you make sure the docker sharness tests pass. Unfortunately, they're disabled on CI at the moment (#6101).

I think we may need to change calls of docker_run "$IMAGE_ID" to docker_run "$IMAGE_ID" daemon.

[kpcyrd]

@Stebalien it still works since the default arguments are ["daemon", "--migrate=true"], running the container without arguments executes ipfs daemon --migrate=true before and after the patch.

What changes is:

Command	Before	After
docker run ipfs/go-ipfs	ipfs daemon --migrate=true	ipfs daemon --migrate=true
docker run ipfs/go-ipfs daemon	ipfs daemon	ipfs daemon
docker run ipfs/go-ipfs --migrate=true	ipfs daemon --migrate=true	ipfs --migrate=true
docker run ipfs/go-ipfs add -w /foo	ipfs daemon add -w /foo	ipfs add -w /foo

[Stebalien]

Thanks!