Merge branch 'master' into TMSS-570

SAS/TMSS/backend/services/websocket/CMakeLists.txt

SAS/TMSS/backend/services/websocket/lib/websocket_service.py

...SS/backend/services/websocket/test/t_websocket_service.py

SAS/TMSS/backend/src/tmss/tmssapp/serializers/common.py

SAS/TMSS/backend/src/tmss/tmssapp/serializers/scheduling.py

...MSS/backend/src/tmss/tmssapp/serializers/specification.py

SAS/TMSS/backend/test/test_utils.py