Installed target name of prometheus export changes in v1.8.0

[owent]

Describe your environment

Build System: CMake

What is the expected behavior?

The installed target name of prometheus export changes from opentelemetry-cpp::prometheus_exporter to opentelemetry-cpp::opentelemetry_exporter_prometheus when using cmake.Should it keep the old name?

What is the actual behavior?

The old codes link opentelemetry-cpp::prometheus_exporter can not compile.

[lalitb]

This was deliberate, to keep it consistent with the naming for other targets. We can indicate it as breaking change in the release document ?

[owent]

This was deliberate, to keep it consistent with the naming for other targets. We can indicate it as breaking change in the release document ?

The target name in v1.8.0 is opentelemetry-cpp::opentelemetry_exporter_prometheus, while other exporters are opentelemetry-cpp::ostream_metrics_exporter, opentelemetry-cpp::otlp_http_metric_exporter, 'opentelemetry-cpp::otlp_grpc_metrics_exporter'.

All targets have opentelemetry-cpp:: prefix, is it redundant to add another opentelemetry_ prefix for prometheus exporter?

[lalitb]

Ah. Got it. I was validating the generated cmake target names, and not the target names in the otel-cpp cmake config. Have fixed it in #1820. Please see if that works.