Bump System.Diagnostics.PerformanceCounter to 8.0

[tomap]

In the last version of Elastic.Apm, you are using System.Diagnostics.PerformanceCounter version 6.0.1

If you were to bump it to version 8.0.0, you'd also bump System.Configuration.ConfigurationManager
which has one less dependency: it does not include a reference to System.Security.Permissions
see:
https://www.nuget.org/packages/System.Configuration.ConfigurationManager/7.0.0#dependencies-body-tab
vs
https://www.nuget.org/packages/System.Configuration.ConfigurationManager/#dependencies-body-tab

It would make Elastic.Apm lighter

Thank you

[thompson-tomo]

@tomap i have already gone and implemented a nicer solution via https://github.com/elastic/apm-agent-dotnet/pull/2308/files which will be in the next release. That MR has eliminated the need for a number of dependencies on the newer TFM'S.

[tomap]

Awesome! Thank you