Handle partial success responses from OTLP export services

[jmacd]

Problem Statement

Following the specification change to add partial success responses, each OTel SDK is encouraged to handle the resulting error message string in an appropriate way, considering existing norms. This requires OTLP v0.19.

Proposed Solution

For each of the Export*ServiceRequest methods used by OTLP Trace and Metrics exporters, construct an error and call the appropriate handler with the error message string and the number of spans/points(/logs) dropped. Future OTel specifications may call for optional treatment of the number of dropped items, but presently that is just additional information to include in the handled error.

[brettmc]

This will be partly implemented by #806.
We'll implement for http+protobuf after open-telemetry/opentelemetry-collector#5816 since we currently have no collector response to work with from that protocol.

[joaopgrassi]

Hi @brettmc should we create a follow up issue to track the implementation for this for http+protobuf?

[jmacd]

Let's please leave this open as long as these responses aren't handled in http/proto and http/json.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.