Update actions/stale action to v7

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/stale	action	major	v3 -> v7

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Release Notes

actions/stale

### [`v7`](https://togithub.com/actions/stale/compare/v6...v7) [Compare Source](https://togithub.com/actions/stale/compare/v6...v7) ### [`v6`](https://togithub.com/actions/stale/compare/v5...v6) [Compare Source](https://togithub.com/actions/stale/compare/v5...v6) ### [`v5`](https://togithub.com/actions/stale/compare/v4...v5) [Compare Source](https://togithub.com/actions/stale/compare/v4...v5) ### [`v4`](https://togithub.com/actions/stale/compare/v3...v4) [Compare Source](https://togithub.com/actions/stale/compare/v3...v4)

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