[PM-10319] - Revoke Non Complaint Users for 2FA and Single Org Policy Enablement (#5037)

- Revoking users when enabling single org and 2fa policies.
- Updated emails sent when users are revoked via 2FA or Single Organization policy enablement

Co-authored-by: Matt Bishop <mbishop@bitwarden.com>
Co-authored-by: Rui Tomé <108268980+r-tome@users.noreply.github.com>

src/Core/AdminConsole/Enums/EventSystemUser.cs

@@ -2,6 +2,7 @@
 
 public enum EventSystemUser : byte
 {
+    Unknown = 0,
     SCIM = 1,
     DomainVerification = 2,
     PublicApi = 3,