[feat] Disable sending emails to Participants team

[vpchung]

Describe The Problem To Be Solved

We have had a couple of instances where a participant would email the entire Challenge Participants team (>500 people), asking a question that should be more geared towards the organizers or Discussion forum instead. Though there is an option on the web portal to disable sending messages:

it does not prevent users already in the team from sending a message.

Ideally, we should make it so that members (other than team managers) cannot send a mass email. I can see this feature being utilized when the Participants team is first created (using the create-challenge command) as well as a standalone function so that it can be called with any team.

(optional) Suggest a Solution

"Hacky" solution I've been using:

import json
team_id = 123  # <-- update this value 
acl = syn.restGET(f"/team/{team_id}/acl")
for member in acl.get('resourceAccess'):
    if member.get("principalId") == team_id:
        member["accessType"] = ['READ']
        break
syn.restPUT("/team/acl", json.dumps(acl))