Span ID always null in Logs | Logs ID injection

**Describe the bug**: I am using logging support which injects correlation ids (trace, transaction, span). However even after running with 100% sample rate I've not been able to get a single log with a Span ID!
Also "maybe" this could be the reason that I am not seeing any logs in trace waterfall

**To Reproduce**

1. Install elastic apm agent version
2. Simply allow logging integration (default)
3. Check in your APM

**Environment (please complete the following information)**
- OS: Linux and Mac
- Python version: 3.9/10
- Framework and version [e.g. Django 2.1]: Should not matter but Sanic v22
- APM Server version: Proprietary Solution
- Agent version: `elastic-apm==6.7.1`

**Additional context**
N/A

Comienza reproduciendo el problema con elastic-apm==6.7.1, Python 3.9 o 3.10 y Sanic v22, con la integración de logging predeterminada habilitada. Inspecciona la integración de logging y el manejo del contexto de trace para determinar por qué Span ID permanece en null; después, verifica que los logs emitidos lo contengan y evalúa si aparecen entradas del trace waterfall.

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