chore(deps): update mcr.microsoft.com/dotnet/sdk docker tag to v9

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
mcr.microsoft.com/dotnet/sdk	stage	major	8.0.404-alpine3.20 -> 9.0.100-alpine3.20

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Release Notes

dotnet/sdk (mcr.microsoft.com/dotnet/sdk)

### [`v9.0.100`](https://redirect.github.com/dotnet/sdk/compare/v8.0.404...v9.0.100) [Compare Source](https://redirect.github.com/dotnet/sdk/compare/v8.0.404...v9.0.100)

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Configuration

📅 Schedule: Branch creation - "before 07:00 on Thursday" in timezone Europe/Oslo, Automerge - At any time (no schedule defined).

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

♻ Rebasing: Whenever PR becomes conflicted, 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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