[repo] move PooledList to Zipkin

[SimonCropp]

Fixes #
Design discussion issue #

Changes

PooledList is only used in Zipkin. so move it there and remove the Share Compile Include complexity

Merge requirement checklist

• CONTRIBUTING guidelines followed (license requirements, nullable enabled, static analysis, etc.)
• Unit tests added/updated
• Appropriate CHANGELOG.md files updated for non-trivial changes
• Changes in public API reviewed (if applicable)

[Kielek]

I am not against this change, as it is used only by this project.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.39%. Comparing base (2828321) to head (7217a7f).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6092   +/-   ##
=======================================
  Coverage   86.39%   86.39%           
=======================================
  Files         257      257           
  Lines       11650    11650           
=======================================
  Hits        10065    10065           
  Misses       1585     1585