Runtime version mismatch with nuget.org on .NET 8 RC2

[Mateus Rodrigues de Morais]

[ Impact ]

 * Users are currently unable to run RID-specific dotnet operations on a .NET
   project, e.g. `dotnet build -r linux-x64`.

 * Since this is a critical bug that could affect real-world scenarios of
   building and publishing RID-specific applications, the fix is being
   backported to Mantic.

 * The upload includes a patch that was suggested by Microsoft [1] and fixes
   the issue by updating the VMR source-built runtime version to the same one
   Microsoft publishes, to prevent the .NET CLI tools from trying to download
   a linux-x64 runtime package that does not exist.

[ Test Plan ]

 * To reproduce the bug, one must install dotnet-sdk-8.0 version
   8.0.100~rc2-0ubuntu1 and run:

   ```
   $ dotnet new console -o Test
   $ cd Test
   $ dotnet build # should work
   $ dotnet build -r linux-x64 # should not work
   ```

 * Version 8.0.100~rc2-0ubuntu2 (in PPA [2]) should have the last
   command working.

[ Where problems could occur ]

 * The patch effectively only changes the version string of the resulting .NET
   source-built runtime. No feature or behavior-related code changes are made.

 * A regression can occur if a third-party software depends on the specific
   version string of the runtime present in 8.0.0~rc2-0ubuntu1.

 * This is highly unlikely as the vast majority of .NET software targets a
   major .NET version, and the diff between both versions is in the build
   section of the version string: 8.0.0-rc.2.23479.6 (new) vs
   8.0.0-rc.2.23475.17 (old).

[1] https://github.com/dotnet/source-build/issues/3673#issuecomment-1779566707
[2] https://launchpad.net/~mateus-morais/+archive/ubuntu/dotnet8-rc2-runtime-version-fix

[Mateus Rodrigues de Morais (mateus-morais)]

The version in PPA [0] with a patch [1] included to fix the error seems to work as expected:

```
$ dotnet publish -r linux-x64
MSBuild version 17.8.0+6cdef4241 for .NET
  Determining projects to restore...
  Restored /root/PackageTest/PackageTest.csproj (in 3.16 sec).
/usr/lib/dotnet/sdk/8.0.100-rc.2.23502.1/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.RuntimeIdentifierInference.targets(311,5): message NETSDK1057: You are using a preview version of .NET. See: https://aka.ms/dotnet-support-policy [/root/PackageTest/PackageTest.csproj]
  PackageTest -> /root/PackageTest/bin/Release/net8.0/linux-x64/PackageTest.dll
  PackageTest -> /root/PackageTest/bin/Release/net8.0/linux-x64/publish/
```

[0] https://launchpad.net/~mateus-morais/+archive/ubuntu/dotnet8-rc2-runtime-version-fix
[1] https://github.com/dotnet/source-build/issues/3673#issuecomment-1779566707

[Launchpad Janitor (janitor)]

This bug was fixed in the package dotnet8 - 8.0.100-8.0.0~rc2-0ubuntu2

---------------
dotnet8 (8.0.100-8.0.0~rc2-0ubuntu2) noble; urgency=medium

  * d/p/0001-Fix-source-built-runtime-version-number.patch: Fix
    source-built runtime version number. (LP: #2040547)

 -- Mateus Rodrigues de Morais <email address hidden> Thu, 26 Oct 2023 08:52:11 -0300

[Steve Langasek (vorlon)]

An upload of dotnet8 to mantic-proposed has been rejected from the upload queue for the following reason: "mantic has 8.0.100-8.0.0-0ubuntu1~23.10.1 which is >> 8.0.100-8.0.0~rc2-0ubuntu2~23.10.1".

[Mateus Rodrigues de Morais (mateus-morais)]

The fix for this issue on Mantic was released as part of dotnet8 8.0.100-8.0.0-0ubuntu1~23.10.1 (GA release)