TMSS-278: add endpoints to get friend of project and current user roles in project plus tests

SAS/TMSS/backend/src/tmss/tmssapp/adapters/keycloak.py

SAS/TMSS/backend/src/tmss/tmssapp/viewsets/permissions.py

SAS/TMSS/backend/src/tmss/tmssapp/viewsets/specification.py

SAS/TMSS/backend/test/t_permissions_project_roles.py