move cli integration tests to the reserved integration folder

[racs4]

also removes the need of executing cargo run on cli tests (when runned in parallel, the tests usually blocked each other because of this), by using assert_cmd library, that runs the specific profile target binary, "mocking" (and also adding assertion properties) to the Command struct.

[racs4]

There's only one "problem" with this approach: the file cli.rs, which contains the cli integration tests, stays in ./tests/ directory, which is the "reserved" directory for cargo integration tests to be run.

But we have the ./test/ directory, which contains some .kdl files with specific code, also for testing purposes. The naming of the two folders seems confusing to me. Should I put the files of ./test/ folders inside of ./tests/<codes or other name>/?