Connect Trace ID between Editoast/Core

[woshilapin]

Derived from https://github.com/osrd-project/osrd-confidential/issues/275.

• [ ] in editoast, forward OTEL context through HTTP headers to all core endpoints
• [ ] in core, catch OTEL context on all API endpoints, coming from editoast

Acceptance criteria

• [ ] in Datadog, we can see traces that goes through editoast and core.

⚠ This ticket has been postponed: connection between editoast and core will change from HTTP to RabbitMQ. The trace's ID will have to go through RabbitMQ eventually, let's not do the work twice.