Update targeting and runtime packs for net9.0 TFM

[ViktorHofer]

Needed for #43015

[am11]

Should it target 9.0.1xx branch, given https://github.com/dotnet/dotnet/blob/52984474a89f4885cda8c5b49c1f01952e7f5a00/global.json#L3

[ViktorHofer]

You mean because the VMR's SDK is behind by one preview release? No, we want nightly 10.0 SDK releases to bring the latest available runtime and targeting packs from the 9.0 release in. I don't think that the VMR would break because of this.

[am11]

Ah, but do you at what point we will define <_NET100..Version? Maybe this is the right time for that.

[ViktorHofer]

I'm doing the minimal change here to unblock #43015. I'm not really familiar with when or how the SDK team updates these versions so I would defer to them on that.

[marcpopMSFT]

We already did the known framework work here: #42969 This list is the downlevel implicit version and we update it to a stable version once we have a released 9.0.0 version. Going to rc2 in the interim is fine.

[ViktorHofer]

@marcpopMSFT The stale P7 version is blocking the net10.0 PR which is why I had to submit this PR. See #43015 (comment)

[am11]

@ViktorHofer sb failed due to missing packages https://dev.azure.com/dnceng-public/public/_build/results?buildId=856092&view=results

  Restored /vmr/eng/finish-source-only.proj (in 97 ms).
  Restored /vmr/eng/extract-sdk-archive.proj (in 97 ms).
/vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj : error NU1102: Unable to find package Microsoft.NETCore.App.Ref with version (= 9.0.0-rc.2.24473.5) [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj : error NU1102:   - Found 7 version(s) in /vmr/prereqs/packages/reference/ [ Nearest version: 8.0.0 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj : error NU1102:   - Found 1 version(s) in /vmr/prereqs/packages/prebuilt/ [ Nearest version: 9.0.0-rc.1.24431.7 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj : error NU1102:   - Found 1 version(s) in /vmr/prereqs/packages/previously-source-built/ [ Nearest version: 9.0.0-preview.7.24405.7 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj : error NU1102: Unable to find package Microsoft.NETCore.App.Ref with version (= 9.0.0-rc.2.24473.5) [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj : error NU1102:   - Found 7 version(s) in /vmr/prereqs/packages/reference/ [ Nearest version: 8.0.0 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj : error NU1102:   - Found 1 version(s) in /vmr/prereqs/packages/prebuilt/ [ Nearest version: 9.0.0-rc.1.24431.7 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj : error NU1102:   - Found 1 version(s) in /vmr/prereqs/packages/previously-source-built/ [ Nearest version: 9.0.0-preview.7.24405.7 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj : error NU1102: Unable to find package Microsoft.AspNetCore.App.Ref with version (= 9.0.0-rc.2.24474.3) [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj : error NU1102:   - Found 2 version(s) in /vmr/prereqs/packages/reference/ [ Nearest version: 8.0.0 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj : error NU1102:   - Found 1 version(s) in /vmr/prereqs/packages/previously-source-built/ [ Nearest version: 9.0.0-preview.7.24406.2 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj : error NU1102:   - Found 0 version(s) in /vmr/prereqs/packages/prebuilt/ [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj : error NU1102: Unable to find package Microsoft.AspNetCore.App.Ref with version (= 9.0.0-rc.2.24474.3) [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj : error NU1102:   - Found 2 version(s) in /vmr/prereqs/packages/reference/ [ Nearest version: 8.0.0 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj : error NU1102:   - Found 1 version(s) in /vmr/prereqs/packages/previously-source-built/ [ Nearest version: 9.0.0-preview.7.24406.2 ] [/vmr/build.proj]
/vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj : error NU1102:   - Found 0 version(s) in /vmr/prereqs/packages/prebuilt/ [/vmr/build.proj]
  Failed to restore /vmr/eng/tools/tasks/Microsoft.DotNet.UnifiedBuild.Tasks/Microsoft.DotNet.UnifiedBuild.Tasks.csproj (in 271 ms).
  Failed to restore /vmr/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj (in 271 ms).

do we need a new source build baseline or just add these packages to one of the package feeds it's searching in?

[ViktorHofer]

@am11 commented in the other PR and asked the soruce-build team. I think we just need to update the Private.SourceBuilt packages.