[WIP] Base2 Exponential histo aggregation

[ethandmd]

Fixes #1391

Changes

Adds Base2 Exponential Histogram Aggregation to the sdk with additional test cases.

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

[linux-foundation-easycla]

• ✅ login: ethandmd / name: ethan (98c97cd)
• ✅ login: euroelessar / name: Ruslan Nigmatullin (81208c0)
• ❌ The email address for the commit (92434dd, 7171c49, c358e5b, 70323b4, 7be4112, 85d43d6, 223ca7b, 849316f) is not linked to the GitHub account, preventing the EasyCLA check. Consult this Help Article and GitHub Help to resolve. (To view the commit's email address, add .patch at the end of this PR page's URL.) For further assistance with EasyCLA, please submit a support request ticket.
• ❌ - login: @felipesantosk / name: Felipe C. Dos Santos . The commit (19fbe9d, a68bd4b, 8a901be, 8fe2a5b, f246d14, 345322b) is not authorized under a signed CLA. Please click here to be authorized. For further assistance with EasyCLA, please submit a support request ticket.

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[codecov]

Codecov Report

Attention: Patch coverage is 62.87425% with 62 lines in your changes missing coverage. Please review.

Project coverage is 88.90%. Comparing base (6175aa0) to head (98c97cd).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
...egation/base2_exponential_histogram_aggregation.cc	71.64%	40 Missing ⚠️
exporters/ostream/src/metric_exporter.cc	0.00%	18 Missing ⚠️
...etry/sdk/metrics/aggregation/default_aggregation.h	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3343      +/-   ##
==========================================
- Coverage   89.56%   88.90%   -0.66%     
==========================================
  Files         210      211       +1     
  Lines        6502     6673     +171     
==========================================
+ Hits         5823     5932     +109     
- Misses        679      741      +62     

Files with missing lines	Coverage Δ
...metry/sdk/metrics/aggregation/aggregation_config.h	100.00% <ø> (ø)
...nclude/opentelemetry/sdk/metrics/data/point_data.h	100.00% <100.00%> (ø)
...etry/sdk/metrics/aggregation/default_aggregation.h	76.55% <0.00%> (-3.97%)	⬇️
exporters/ostream/src/metric_exporter.cc	79.14% <0.00%> (-11.77%)	⬇️
...egation/base2_exponential_histogram_aggregation.cc	71.64% <71.64%> (ø)

... and 3 files with indirect coverage changes

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