fn check_policy_signature(
pdu_json: &CanonicalJsonObject,
room_version: &RoomVersionId,
via: &ServerName,
public_key: &Base64,
) -> PolicyCheckfn check_policy_signature(
pdu_json: &CanonicalJsonObject,
room_version: &RoomVersionId,
via: &ServerName,
public_key: &Base64,
) -> PolicyCheck