[Bug]: Streaming capability check uses deprecated task/resubscribe method

### What happened?

`task/resubscribe` is no longer in the spec. However, `test_tasks_resubscribe` and `test_tasks_resubscribe_nonexistent` still attempt to send it as a method and test for its capability.

### Code of Conduct

- [x] I agree to follow this project's Code of Conduct

Look for the tests `test_tasks_resubscribe` and `test_tasks_resubscribe_nonexistent` in the test suite. They likely send a deprecated `task/resubscribe` method. Find where the streaming capability check is performed and update it to use the current spec method. Run these specific tests to verify they pass after the change.

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