Flaky test TestGdmModel/New_password_cannot_change_because_not_respecting_rules_with_preset_PAM_user_and_server_side_broker_and_authMode_selection

https://github.com/ubuntu/authd/actions/runs/16645594210/job/47105388753?pr=1027#step:3:41626

```
2025-07-31T09:56:36.8883562Z gdmmodel_test.go:2671:
2025-07-31T09:56:36.8884066Z Error Trace: /home/runner/work/authd/authd/tmp.psCAUeCiz0/source/obj-x86_64-linux-gnu/src/github.com/ubuntu/authd/pam/internal/gdm_test/gdm_utils.go:22
2025-07-31T09:56:36.8884542Z /home/runner/work/authd/authd/tmp.psCAUeCiz0/source/obj-x86_64-linux-gnu/src/github.com/ubuntu/authd/pam/internal/adapter/gdmmodel_test.go:2671
2025-07-31T09:56:36.8884712Z Error: Not equal:
2025-07-31T09:56:36.8885517Z expected: "[\n {\n \"access\": \"retry\",\n \"msg\": \"The password is shorter than 8 characters\"\n },\n {\n \"access\": \"retry\",\n \"msg\": \"The password fails the dictionary check - it is based on a dictionary word\"\n },\n {\n \"access\": \"granted\",\n \"msg\": \"Hi GDM, it's a pleasure to change your password!\"\n }\n]"
2025-07-31T09:56:36.8886247Z actual : "[\n {\n \"access\": \"retry\",\n \"msg\": \"The password fails the dictionary check - it is based on a dictionary word\"\n },\n {\n \"access\": \"retry\",\n \"msg\": \"The password is shorter than 8 characters\"\n },\n {\n \"access\": \"granted\",\n \"msg\": \"Hi GDM, it's a pleasure to change your password!\"\n }\n]"
2025-07-31T09:56:36.8886368Z
2025-07-31T09:56:36.8886434Z Diff:
2025-07-31T09:56:36.8886518Z --- Expected
2025-07-31T09:56:36.8886685Z +++ Actual
2025-07-31T09:56:36.8886768Z @@ -3,3 +3,3 @@
2025-07-31T09:56:36.8886852Z "access": "retry",
2025-07-31T09:56:36.8886985Z - "msg": "The password is shorter than 8 characters"
2025-07-31T09:56:36.8887263Z + "msg": "The password fails the dictionary check - it is based on a dictionary word"
2025-07-31T09:56:36.8887331Z },
2025-07-31T09:56:36.8887406Z @@ -7,3 +7,3 @@
2025-07-31T09:56:36.8887484Z "access": "retry",
2025-07-31T09:56:36.8887692Z - "msg": "The password fails the dictionary check - it is based on a dictionary word"
2025-07-31T09:56:36.8887810Z + "msg": "The password is shorter than 8 characters"
2025-07-31T09:56:36.8887875Z },
2025-07-31T09:56:36.8888305Z Test: TestGdmModel/New_password_cannot_change_because_not_respecting_rules_with_preset_PAM_user_and_server_side_broker_and_authMode_selection
```

The test case is defined [here](https://github.com/ubuntu/authd/blob/e1d3766599c9c76f957d631d866ca211b32a3fc7/pam/internal/adapter/gdmmodel_test.go#L491-L556).

It looks like the events that are being sent are not handled in order.