/pr fix does not close feedback on the PR

### Describe the bug

I use `/pr fix all` in the Copilot CLI to address feedback from copilot reviews on my GitHub PR. It fixes, commits, pushes, but it doesn't close the feedback comments in the PR. I have to go click on each manually.

If that's intentional, please add an option to do it. I have to do it on every one.

### Affected version

CLI 1.0.5.

### Steps to reproduce the behavior

_No response_

### Expected behavior

_No response_

### Additional context

_No response_

Start by tracing the `/pr fix all` flow in Copilot CLI and its handling of feedback comments on GitHub pull requests. Reproduce the behavior described for CLI 1.0.5, then verify that the intended comment-closing behavior or an explicit option is reflected in the pull request.

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