RUM-5757 benchmark: Collect Session Replay Record Spans

[maxep]

What and why?

Do not merge: Tracer perfs skew the measures

Collection traces of the recording phase of Session Replay.

How?

• Create an OpenTelemetry tracer
• Inject the tracer in the SDK
• Start/Stop spans of recorders.

Review checklist

• [x] Feature or bugfix MUST have appropriate tests (unit, integration)
• [x] Make sure each commit and the PR mention the Issue number or JIRA reference
• [ ] Add CHANGELOG entry for user facing changes