Fix: example queued_interceptor_csrftoken.dart

[seunghwanly]

Provide a more suitable example for queued_interceptor_csrftoken.dart

New Pull Request Checklist

• I have read the Documentation
• I have searched for a similar pull request in the project and found none
• I have updated this branch with the latest main branch to avoid conflicts (via merge from master or rebase)
• I have added the required tests to prove the fix/feature I'm adding
• I have updated the documentation (if necessary)
• I have run the tests without failures
• I have updated the CHANGELOG.md in the corresponding package

Additional context and info (if any)

This example adds 2 different QueuedInterceptorsWrapper and the last one handles onError to update csrf token.

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fixes #2128

[seunghwanly]

I'll check the type exceptions in test_suite_test.dart

[AlexV525]

The failing tests should be random, caused by the httpbun, fyi.

[AlexV525]

Someday we'd expect to have a unit test with token updates.

[seunghwanly]

Someday we'd expect to have a unit test with token updates.

I'll also be on the lookout for cases to write unit tests for token refresh.