add report_cb to format log messages in composite propagator

[tsloughter]

No description provided.

[codecov]

Codecov Report

Merging #355 (c88bb51) into main (e518fcc) will decrease coverage by 0.01%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main     #355      +/-   ##
==========================================
- Coverage   33.56%   33.55%   -0.02%     
==========================================
  Files          56       56              
  Lines        4561     4563       +2     
==========================================
  Hits         1531     1531              
- Misses       3030     3032       +2     

Flag	Coverage Δ
api	68.44% <0.00%> (-0.47%)	⬇️
elixir	16.36% <0.00%> (-0.11%)	⬇️
erlang	33.49% <0.00%> (-0.02%)	⬇️
exporter	21.57% <ø> (ø)
sdk	77.10% <ø> (+0.19%)	⬆️
zipkin	2.59% <ø> (ø)

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Impacted Files	Coverage Δ
...try_api/src/otel_propagator_text_map_composite.erl	41.17% <0.00%> (-5.50%)	⬇️
apps/opentelemetry_api/src/otel_utils.erl	0.00% <ø> (ø)

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