Refactor tox.ini to prepare parallelized jobs

Refactor tox.ini to prepare parallelized jobs

- split py3 profiles into several profiles
  and regroup tests by OpenROADM devices version
- separate the controller build from tests themselves in a dedicated
  profile
- use "depends" to state profiles dependencies.
  This is necessary so that tox can order tests sequences
  and decides which jobs can be run in parallel.
  This parameter requires tox versions >= 3.7.0

NB: at this stage, tests can no more be run standalone from a dedicated
tox profile.

JIRA: TRNSPRTPCE-482
Signed-off-by: Guillaume Lambert <guillaume.lambert@orange.com>
Change-Id: I8d583f01003c4d9ee690d866ff602757392c3304