EDUCATOR-4876: Correctly handle 'None' as a valid max_team_size (#23038)

common/lib/xmodule/xmodule/course_module.py

common/lib/xmodule/xmodule/tests/test_course_module.py

...ngoapps/teams/static/teams/js/spec/views/my_teams_spec.js

lms/djangoapps/teams/static/teams/js/views/my_teams.js

lms/djangoapps/teams/static/teams/js/views/team_card.js

lms/djangoapps/teams/static/teams/js/views/team_utils.js

lms/djangoapps/teams/static/teams/js/views/teams.js

lms/djangoapps/teams/static/teams/js/views/teams_tab.js

lms/djangoapps/teams/static/teams/js/views/topic_teams.js

openedx/core/lib/teams_config.py

openedx/core/lib/tests/test_teams_config.py