Update mcr.microsoft.com/dotnet/aspnet Docker tag to v9

This PR contains the following updates:

Package	Type	Update	Change
mcr.microsoft.com/dotnet/aspnet	final	major	`8.0.11-alpine3.20` -> `9.0.0-alpine3.20`

Release Notes

dotnet/aspnetcore (mcr.microsoft.com/dotnet/aspnet)

### [`v9.0.0`](https://redirect.github.com/dotnet/aspnetcore/compare/v8.0.11...v9.0.0) [Compare Source](https://redirect.github.com/dotnet/aspnetcore/compare/v8.0.11...v9.0.0)

Configuration

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Altinn / altinn-file-scan

Update mcr.microsoft.com/dotnet/aspnet Docker tag to v9 #203

Release Notes

Configuration

Quality Gate passed