Adds tests for submitted_flags
Adds tests for submitted_flags

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