[SDK] Invalid thread instrumentation in PeriodicExportingMetricReader

[marcalff]

Fixes #3840

Changes

Please provide a brief description of the changes here.

• Remove PeriodicExportingMetricReaderRuntimeOptions::collect_thread_instrumentation
• This fixes a regression introduced by [SDK] Optimize PeriodicExportingMetricReader Thread Usage #3383, a thread should have only one instrumentation.

For significant contributions please make sure you have completed the following items:

• CHANGELOG.md updated for non-trivial changes
• Unit tests have been added
• Changes in public API reviewed

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 89.97%. Comparing base (437ad43) to head (54974c5).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...metrics/export/periodic_exporting_metric_reader.cc	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3842      +/-   ##
==========================================
+ Coverage   89.96%   89.97%   +0.02%     
==========================================
  Files         225      225              
  Lines        7169     7168       -1     
==========================================
  Hits         6449     6449              
+ Misses        720      719       -1     

Files with missing lines	Coverage Δ
...metrics/export/periodic_exporting_metric_reader.cc	77.42% <50.00%> (+0.83%)	⬆️

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[ThomsonTan]

LGTM, thanks for the fix.