Remove Jaeger example and OpenTracing support

[dmatej]

When looking into #6056, I have found that the OpenTracing project was discontinued, see

• 🛑 Deprecating OpenTracing  opentracing/specification#163
• https://github.com/opentracing - All repositories are archived, project abandoned to OpenTelemetry.

Jaeger is still alive, but I guess completely changed APIs, so we would have to redo the whole thing.

• https://medium.com/jaegertracing/jaeger-v2-released-09a6033d1b10
• https://www.jaegertracing.io/download/

"Jaeger v1 has reached end-of-life on December 31, 2025 and will no longer receive updates."

For now we should remove:

    <artifactId>open-tracing</artifactId>
    <packaging>jar</packaging>
    <name>jersey-examples-open-tracing</name>

and

    <groupId>org.glassfish.jersey.incubator</groupId>
    <artifactId>jersey-open-tracing</artifactId>