chore: move Benchmarks for Sentry.Extensions.Logging into separate project

[Flash0ver]

Summary

Move the Benchmark for Sentry.Extensions.Logging into a new Sentry.Extensions.Logging.Benchmarksproject.

Remarks

In #4308, I broke the SentryCore.slnf filtered solution, by adding a dependency to Sentry.Extensions.Logging in the Sentry.Benchmarks project.
See eadf5f2#diff-a68c64a5b74a24eb0d8d7d04aeb893acd2358768b2e0efe3a747d79199a0bea1R17.

Fixing this problem (without pulling in a bunch of projects into SentryCore.slnf) by separating the Benchmarks for Microsoft.Extensions.Logging into a new separate Benchmarking project.

This structure also now mimics /tests/, where we have one Test-Project per Project-Under-Test.

[github-actions]

Semver Impact of This PR

⚪ None (no version bump detected)

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[Flash0ver]

note: remove redundant comment

<UseSentryCLI>false</UseSentryCLI> was removed via 91b22a9#diff-f431a929d80ac5e052346ee209d3600c6f7385325f3811b74dbba9bf66c21054L7, but the comment remained.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 74.07%. Comparing base (3d46788) to head (1f35f7e).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5146   +/-   ##
=======================================
  Coverage   74.07%   74.07%           
=======================================
  Files         501      501           
  Lines       18111    18111           
  Branches     3521     3521           
=======================================
  Hits        13415    13415           
  Misses       3837     3837           
  Partials      859      859           

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[Flash0ver]

note: removing, as already declared in "parent" Directory.Build.props

[Flash0ver]

thought: code duplication

This file pretty much is a duplicate from the existing benchmarks/Sentry.Benchmarks/Program.cs, except for the namespace ... which we could argue is fine to keep in the default namespace of the project when using Top-Level-Statements instead.

Should we have more Benchmark-Projects in the future, we could have a single .cs file, that we <Compile Include="..." /> across all projects.
Or we do that right away already.