Merge branch 'L2SS-240-integration-testing' into 'master'

.gitlab-ci.yml

CDB/integration_ConfigDb.json

devices/.stestr.conf

devices/integration_test/README.md

devices/integration_test/__init__.py

devices/integration_test/base.py

devices/integration_test/client/__init__.py

devices/integration_test/client/test_apsct_sim.py

devices/integration_test/client/test_sdptr_sim.py

devices/integration_test/devices/__init__.py

devices/integration_test/devices/test_device_pcc.py

devices/integration_test/devices/test_device_sdp.py

devices/tox.ini

docker-compose/integration-test.yml

sbin/run_integration_test.sh