./cli.py prepare should reload the broker option from the env

[msimonin]

Currently calling ./cli.py prepare from the command line applies the default configuration of the broker (qdr complete graph of size 4). We don't want to run in this situation :

./cli.py deploy rabbitmq
./cli.py destroy
# The following will install qdr instead of rabbitmq (usually we don't want to change the bus when iterating)
./cli.py prepare 

[jrbalderrama]

What is the status of this issue. It looks like it was already addressed in the code with

ombt-orchestrator/orchestrator/cli.py

Line 53 in ac7000b

t.prepare(driver=driver, env=env)

and this

ombt-orchestrator/orchestrator/tasks.py

Line 262 in ac7000b

config = env["config"]["drivers"].get(driver, DRIVER)