fix: Move report_cheater to flags to avoid circular import

flags.py

@@ -1,7 +1,14 @@
 from CTFd.plugins.flags import BaseFlag
 from CTFd.utils.user import get_current_user
+from CTFd.models import  db
+from .models import CheaterTeams
 
-from . import report_cheater
+
+
+def report_cheater(challenge_id: int, cheater_id: int, helper_id: int, flag_id: int):
+    cheater = CheaterTeams(challenge_id, cheater_id, helper_id, flag_id)
+    db.session.add(cheater)
+    db.session.commit()
 
 
 class PersonalFlag(BaseFlag):