[.github/workflows] Update peter-evans/create-pull-request action to v7

[MaxWinterstein]

This PR contains the following updates:

Package	Type	Update	Change
peter-evans/create-pull-request	action	major	v6 -> v7

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Release Notes

peter-evans/create-pull-request (peter-evans/create-pull-request)

### [`v7`](https://redirect.github.com/peter-evans/create-pull-request/compare/v6...v7) [Compare Source](https://redirect.github.com/peter-evans/create-pull-request/compare/v6...v7)

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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