Removed team_captains from teams with no users in fixtures
Removed team_captains from teams with no users in fixtures

mitre-cyber-academy/ctf-scoreboard,mitre-cyber-academy/ctf-scoreboard,mitre-cyber-academy/ctf-scoreboard,mitre-cyber-academy/registration-app,mitre-cyber-academy/ctf-scoreboard,mitre-cyber-academy/registration-app,mitre-cyber-academy/registration-app