[exporter/elasticsearch] Support exponential histogram

[carsonip]

Component(s)

exporter/elasticsearch

Is your feature request related to a problem? Please describe.

There is no exponential histogram support in elasticsearch exporter now. It means exponential histograms are ignored. As Elasticsearch does not support native exponential histogram at the moment, exponential histograms in opentelemetry should be converted to T-digest and indexed.

Describe the solution you'd like

Convert to exponential histograms to Elasticsearch compatible format and index them.

Describe alternatives you've considered

No response

Additional context

No response

[github-actions[bot]]

Pinging code owners:

• exporter/elasticsearch: @JaredTan95 @ycombinator @carsonip

  See Adding Labels via Comments if you do not have permissions to add labels yourself.

[crobert-1]

This makes sense to me, and the issue was filed by code owner. Removing needs triage.