Update dotnet monorepo to v9 (major)

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
mcr.microsoft.com/dotnet/aspnet	final	major	8.0 -> 9.0
mcr.microsoft.com/dotnet/sdk	stage	major	8.0 -> 9.0

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Configuration

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[omgitsjan]

nope, we just want to use LTS

[renovate]

Renovate Ignore Notification

Because you closed this PR without merging, Renovate will ignore this update. You will not get PRs for any future 9.x releases. But if you manually upgrade to 9.x then Renovate will re-enable minor and patch updates automatically.

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