[FIX] mail: fix race condition in mail tour

If the check for messaging happens after switching from channel to starred
(where there is no composer) it would crash when using `this`.

closes odoo/odoo#104392

X-original-commit: d3091762cc5769ed13b5a828769bcd03f440a8f8
Signed-off-by: Alexandre Kühn (aku) <aku@odoo.com>

addons/mail/static/src/models/composer_view.js

@@ -573,8 +573,8 @@ registerModel({
                 const message = messaging.models['Message'].insert(
                     messaging.models['Message'].convertData(messageData)
                 );
-                if (this.messaging.hasLinkPreviewFeature && !message.isBodyEmpty) {
-                    this.messaging.rpc({
+                if (messaging.hasLinkPreviewFeature && !message.isBodyEmpty) {
+                    messaging.rpc({
                         route: `/mail/link_preview`,
                         params: {
                             message_id: message.id