Update actions/stale action to v9

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/stale	action	major	v8 -> v9

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Release Notes

actions/stale (actions/stale)

### [`v9`](https://togithub.com/actions/stale/compare/v8...v9) [Compare Source](https://togithub.com/actions/stale/compare/v8...v9)

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