Fix exiting in integrated-devnet

[FabijanC]

Usage related changes

• Log message if integrated-devnet exits with status code not equal to zero.

Development related changes

• Added tests that expect integrated-devnet failure (if wrong cli parameters or address occupied, for both venv and docker).
• Removed the --detach flag from the dockerized integrated devnet
• It is still handled correctly, but allows us to use the subprocess return by the docker (with --detach, it would spawn the container in background and that spawner process would die immediatelly after spawning)
• Drew inspiration from fix: add error checks for integrated devnet process #133.

Checklist:

• Formatted the code
• No linter errors
• Tried to avoid introducing linter warnings
• Performed a self-review of the code
• Rebased to the last commit of the target branch (or merged it into my branch)
• Documented the changes
• Updated the test directory
• All tests are passing

[Nathan-SL]

Great work!