Fix attribute filtering for synchronous instruments.

[lalitb]

Fixes #2468

Changes

Please provide a brief description of the changes here.

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

Attention: 10 lines in your changes are missing coverage. Please review.

Comparison is base (497eaf4) 87.12% compared to head (12f3ee2) 87.02%.
Report is 1 commits behind head on main.

❗ Current head 12f3ee2 differs from pull request most recent head 3105173. Consider uploading reports for the commit 3105173 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2472      +/-   ##
==========================================
- Coverage   87.12%   87.02%   -0.10%     
==========================================
  Files         200      202       +2     
  Lines        6109     6129      +20     
==========================================
+ Hits         5322     5333      +11     
- Misses        787      796       +9     

Files	Coverage Δ
...ude/opentelemetry/sdk/metrics/data/exemplar_data.h	0.00% <ø> (ø)
...nclude/opentelemetry/sdk/metrics/exemplar/filter.h	100.00% <ø> (ø)
...nclude/opentelemetry/sdk/metrics/observer_result.h	100.00% <100.00%> (+7.70%)	⬆️
...entelemetry/sdk/metrics/state/attributes_hashmap.h	92.31% <100.00%> (-0.11%)	⬇️
...ntelemetry/sdk/metrics/state/sync_metric_storage.h	86.37% <100.00%> (ø)
...ntelemetry/sdk/metrics/view/attributes_processor.h	85.00% <ø> (-5.00%)	⬇️
...sdk/metrics/state/filtered_ordered_attribute_map.h	57.15% <57.15%> (ø)
...rc/metrics/state/filtered_ordered_attribute_map.cc	58.83% <58.83%> (ø)

... and 3 files with indirect coverage changes