[IMP] mail: fix race condition in tests

Probably introduced in PR changing rendering of chatter in form renderer that
changed timers in unfortunate situations.

Open form view utils was missing an await on (chatter container) render, but the
issue was not perceptible before.

closes odoo/odoo#95003

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

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

@@ -28,7 +28,7 @@ registerModel({
          * @returns {FieldCommand}
          */
         _computePersonaImStatusIconView() {
-            return this.messaging.partnerRoot.isImStatusSet ? insertAndReplace() : clear();
+            return this.messaging.partnerRoot && this.messaging.partnerRoot.isImStatusSet ? insertAndReplace() : clear();
         },
     },
     fields: {

addons/mail/static/tests/helpers/test_utils.js

@@ -564,7 +564,7 @@ async function start(param0 = {}) {
     pyEnv.mockServer = MockServer.currentMockServer;
     const openView = async (action, options) => {
         action['type'] = action['type'] || 'ir.actions.act_window';
-        return doAction(webClient, action, { props: options });
+        await afterNextRender(() => doAction(webClient, action, { props: options }));
     };
     await waitUntilEventPromise;
     return {