[2/6] introspection: implement OTLP support for metrics and traces

[hdonnay]

Stack:

• https://github.com/quay/clair/pull/2101
• https://github.com/quay/clair/pull/2102
• https://github.com/quay/clair/pull/1817
• https://github.com/quay/clair/pull/2103
• https://github.com/quay/clair/pull/2104
• https://github.com/quay/clair/pull/1974

---

introspection: implement OTLP support for metrics and traces

This should allow a Clair instance to use the "native" OpenTelemetry transport for metrics and traces.

Some parts of Clair and Claircore are directly instrumented with Prometheus, and so the OTLP support should be considered beta-quality.

Signed-off-by: Hank Donnay hdonnay@redhat.com