<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** Resolves#45700
Not a product change. This PR will allow us to run the workflow
manually. After ~2 weeks, if there are no issues, we'll make it
automatic.
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **New Features**
* Added automated workflow to identify and close stale issues created by
Fleet team members, with dry-run capability and operation limits.
* Added system to build and maintain a deduplicated list of Fleet team
member handles from GitHub organization and repository history.
* **Tests**
* Added comprehensive test suites for stale issue management and handle
list generation with mock GitHub API interactions and boundary condition
coverage.
<!-- review_stack_entry_start -->
[](https://app.coderabbit.ai/change-stack/fleetdm/fleet/pull/45530?utm_source=github_walkthrough&utm_medium=github&utm_campaign=change_stack)
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<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Victor Lyuboslavsky
d051cf082b
