Fix MSBuild race condition in StartupHook build reference

[Copilot]

Summary

Parallel builds were hitting a file access race condition on Microsoft.Diagnostics.Monitoring.StartupHook.dll. Added OutputItemType="" and SkipGetTargetFrameworkProperties="true" to the ProjectReference with Targets="Publish" to prevent MSBuild from creating cross-project dependencies that cause simultaneous file access. Additionally, explicitly set TargetFramework=$(StartupHookTargetFramework) in AdditionalProperties to ensure proper target framework resolution when using SkipGetTargetFrameworkProperties="true".

Release Notes Entry

Original prompt

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This section details on the original issue you should resolve

<issue_title>Fix known race condition in build</issue_title>
<issue_description>#8555 (comment)</issue_description>

Comments on the Issue (you are @copilot in this section)

@wiktork ##[error]CSC(0,0): error CS2012: (NETCORE_ENGINEERING_TELEMETRY=Build) Cannot open 'D:\a\_work\1\s\artifacts\obj\Microsoft.Diagnostics.Monitoring.StartupHook\Release\net6.0\Microsoft.Diagnostics.Monitoring.StartupHook.dll' for writing -- The process cannot access the file 'D:\a\_work\1\s\artifacts\obj\Microsoft.Diagnostics.Monitoring.StartupHook\Release\net6.0\Microsoft.Diagnostics.Monitoring.StartupHook.dll' because it is being used by another process.; file may be locked by 'csc' (2012)

• Fixes Fix known race condition in build #8556

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