Publish metric on distribution availability

[bhautikpip]

Publish metric on distribution availability

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Description of changes:

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[codecov-io]

Codecov Report

Merging #279 (965a5ae) into master (f5f41fb) will decrease coverage by 0.58%.
The diff coverage is n/a.

❗ Current head 965a5ae differs from pull request most recent head 93641d5. Consider uploading reports for the commit 93641d5 to get more accurate results

@@            Coverage Diff             @@
##           master     #279      +/-   ##
==========================================
- Coverage   79.52%   78.93%   -0.59%     
==========================================
  Files          83       83              
  Lines        3277     3195      -82     
==========================================
- Hits         2606     2522      -84     
- Misses        671      673       +2     

Impacted Files	Coverage Δ
aws_xray_sdk/core/async_context.py	84.74% <0.00%> (-6.78%)	⬇️
aws_xray_sdk/core/sampling/connector.py	47.94% <0.00%> (-2.71%)	⬇️
aws_xray_sdk/core/emitters/udp_emitter.py	61.11% <0.00%> (-2.05%)	⬇️
aws_xray_sdk/core/sampling/reservoir.py	57.69% <0.00%> (-1.57%)	⬇️
aws_xray_sdk/ext/dbapi2.py	79.54% <0.00%> (-1.31%)	⬇️
aws_xray_sdk/core/sampling/sampling_rule.py	90.90% <0.00%> (-1.05%)	⬇️
aws_xray_sdk/core/recorder.py	86.08% <0.00%> (-1.04%)	⬇️
aws_xray_sdk/core/sampling/sampler.py	63.01% <0.00%> (-0.99%)	⬇️
aws_xray_sdk/core/sampling/local/sampling_rule.py	93.61% <0.00%> (-0.83%)	⬇️
aws_xray_sdk/sdk_config.py	92.30% <0.00%> (-0.80%)	⬇️
... and 13 more

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