Fix wrong display of MFA email.

There was some wrong logic regarding the display of which email is
configured to be used for the email MFA. This is now fixed.

Resolves #1878

src/api/core/two_factor/email.rs

@@ -80,14 +80,16 @@ fn get_email(data: JsonUpcase<PasswordData>, headers: Headers, conn: DbConn) ->
         err!("Invalid password");
     }
 
-    let type_ = TwoFactorType::Email as i32;
-    let enabled = match TwoFactor::find_by_user_and_type(&user.uuid, type_, &conn) {
-        Some(x) => x.enabled,
-        _ => false,
+    let (enabled, mfa_email) = match TwoFactor::find_by_user_and_type(&user.uuid, TwoFactorType::Email as i32, &conn) {
+        Some(x) => {
+            let twofactor_data = EmailTokenData::from_json(&x.data)?;
+            (true, json!(twofactor_data.email))
+        }
+        _ => (false, json!(null)),
     };
 
     Ok(Json(json!({
-        "Email": user.email,
+        "Email": mfa_email,
         "Enabled": enabled,
         "Object": "twoFactorEmail"
     })))