[Code Health] Include what you use, part 6

[marcalff]

Contributes to #2054

Changes

• The github CI was upgraded recently to run on Ubuntu 24.04.1, a bump from 22.04.5
• As a result, the iwyu tool was upgraded to version 8.21-1build2, a bump from 8.17-1
• include-what-you-use reports more diagnostics in version 8.21, causing the number of warnings to increase, after the upgrade in CI runners.

This fix resolves the new warnings reported by iwyu 8.21.

The warning count was 177 before this fix, it is now down to 5 (to resolve separately).

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

[netlify]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.16%. Comparing base (c33f800) to head (695f500).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3216   +/-   ##
=======================================
  Coverage   88.16%   88.16%           
=======================================
  Files         198      198           
  Lines        6224     6224           
=======================================
  Hits         5487     5487           
  Misses        737      737           

Files with missing lines	Coverage Δ
exporters/memory/src/in_memory_metric_data.cc	85.00% <ø> (ø)
...xporters/memory/test/in_memory_metric_data_test.cc	100.00% <ø> (ø)
...ters/memory/test/in_memory_metric_exporter_test.cc	100.00% <ø> (ø)
...orters/memory/test/in_memory_span_exporter_test.cc	100.00% <ø> (ø)
exporters/ostream/src/log_record_exporter.cc	97.06% <ø> (ø)
...porters/ostream/src/log_record_exporter_factory.cc	100.00% <ø> (ø)
exporters/ostream/test/ostream_log_test.cc	96.18% <ø> (ø)
exporters/ostream/test/ostream_metric_test.cc	100.00% <ø> (ø)
exporters/ostream/test/ostream_span_test.cc	100.00% <ø> (ø)
sdk/src/logs/batch_log_record_processor.cc	89.29% <ø> (ø)
... and 17 more