Handle Nuke .NET 9 preview issue (#6130)

## Summary of changes

- Adds workaround for case where .NET 9 (preview) SDK is installed
lately.

## Reason for change

Fixes case where Nuke no longer works if you install the .NET 9  SDK

## Implementation details

Currently we have a global.json which enforces that we use the .NET
8.0.100 SDK for building _in general_. However, we have to use the .NET
7 SDK for running the Nuke project specifically when we're building the
Linux x64 _native_ components.

> This is because .NET 8 _doesn't_ support CentOS 7 and can't run there,
but we _have_ to use CentOS 7 currently for technical reasons.

We worked around this previously by specifically opting in to
major-version rollforward in the Nuke project. Unfortunately, Nuke
doesn't work out of the box with .NET 9 because of the [binary

formatter](https://learn.microsoft.com/en-gb/dotnet/standard/serialization/binaryformatter-security-guide)
removal. Consequently we have to make sure we _don't_ roll forward to
.NET 9 in that case.

The solution is pretty simple:
- Explicitly use .NET 8 _without_ roll forward in general
- Set an env var in the CentOS7 dockerfile `USE_NATIVE_SDK_VERSION=true`
which switches the Nuke project to build and run on .NET 7 explicitly

## Test coverage

Tested locally that it fixes the .NET 9 issue, this is the test for CI

## Other details

~The side-quest here was updating Nuke as it was quiet out of date. I
_thought_ it might be required, and it required fixing a _bunch_ of
warnings and breaking changes, so figured it would make sense to just do
the work here at the same time~ This ended up being a horrible pit of
errors so I abandoned it as it seems to be unnecessary.

.azure-pipelines/ultimate-pipeline.yml

@@ -504,7 +504,7 @@ stages:
         build: true
         target: builder
         baseImage: "universal"
-        useNativeSdkVersion: true
+        useNativeSdkVersion: false
         command: "Clean BuildNativeLoader BuildNativeWrapper ExtractDebugInfoLinux"
         retryCountForRunCommand: 1
 

tracer/build/_build/_build.csproj

@@ -2,10 +2,10 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework Condition="$(USE_NATIVE_SDK_VERSION) == 'true'">net7.0</TargetFramework>
     <TargetFramework Condition="$(OS.StartsWith('Windows')) AND '$(NUKE_NOTIFY)' != ''">$(TargetFramework)-windows10.0.19041</TargetFramework>
     <DefineConstants Condition="$(OS.StartsWith('Windows')) AND '$(NUKE_NOTIFY)' != ''">$(DefineConstants);NUKE_NOTIFY</DefineConstants>
-    <RollForward>LatestMajor</RollForward>
     <RootNamespace></RootNamespace>
     <!-- NU* are workaround for Rider bug: https://youtrack.jetbrains.com/issue/RIDER-103207/Cannot-suppress-vulnerable-package-errors -->
     <NoWarn>CS0649;CS0169;SA1652;NU1901;NU1902;NU1903;NU1904</NoWarn>

tracer/build/_build/docker/centos7.dockerfile

@@ -78,6 +78,8 @@ ENV \
 
 FROM base as builder
 
+ENV USE_NATIVE_SDK_VERSION=true
+
 # Copy the build project in and build it
 COPY *.csproj *.props *.targets /build/
 RUN dotnet restore /build
@@ -104,6 +106,8 @@ RUN if [ "$(uname -m)" = "x86_64" ]; \
     && rm dotnet-install.sh
 
 
+ENV USE_NATIVE_SDK_VERSION=true
+
 # Copy the build project in and build it
 COPY *.csproj *.props *.targets /build/
 RUN dotnet restore /build

tracer/build/_build/docker/universal.dockerfile

@@ -55,6 +55,7 @@ RUN ln -s `which clang-16` /usr/bin/clang  && \
 
 ENV \
     DOTNET_ROLL_FORWARD_TO_PRERELEASE=1 \
+    USE_NATIVE_SDK_VERSION=true \
     CXX=clang++ \
     CC=clang