I get this error when the build is started
/nix/store/0f43yfx91hg74bcp66qkbp97zv3ln27i-dotnet-sdk-6.0.413/sdk/6.0.413/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.TargetFrameworkInference.targets(144,5): error NETSDK1045: The current .NET SDK does not support targeting .NET 9.0. Either target .NET 6.0 or lower, or use a version of the .NET SDK that supports .NET 9.0. [/app/src/QR_BlinkShare.Application.Contracts/QR_BlinkShare.Application.Contracts.csproj]

my docker file is:

# Use .NET 9.0 SDK for building the application

FROM mcr.microsoft.com/dotnet/sdk:9.0 AS build-env

WORKDIR /src

# Force a fresh restore by copying everything at once

COPY . .

# Ensure restore always runs fresh

RUN dotnet restore --force

# Build and publish

WORKDIR /src/QR_BlinkShare.HttpApi.Host

RUN dotnet publish -c Release -o /app/out --no-restore

# Use .NET 9.0 Runtime to run the application

FROM mcr.microsoft.com/dotnet/aspnet:9.0 AS runtime

WORKDIR /app

COPY --from=build-env /app/out .

# Start the application

ENTRYPOINT ["dotnet", "QR_BlinkShare.HttpApi.Host.dll"]