Microsoft Teams: Block a user for your organization

With the availability of the delete API (removeallaccessforuser API), it does not stop the malicious user from resending the message to the same victim. To help prevent that, a block user API will allow the admin to block the malicious user from reaching out again. To make this even more effective, we will utilize a similar feature as the allow/block list in federation to block the malicious user from the entire organization.