[PATCH] Fix otel requests

[johncalesp]

I noticed that even if the flag OTEL_ENABLED is disabled, when you call tracer.start_as_current_span directly, it looks like otel gets enable with default params and tries to send the content to host='localhost', port=4318.
To fix this, I used nullcontext in case the flag is not enable and so we can avoid this error.
I tested on dlcluster and it works.

[Copilot]

Pull Request Overview

This PR fixes an issue where OpenTelemetry (OTEL) would initialize with default settings and attempt to send telemetry data to localhost:4318 even when the OTEL_ENABLED flag was disabled. The fix uses nullcontext() as a no-op context manager when telemetry is disabled, preventing unwanted OTEL initialization and network calls.

Key changes:

• Added conditional telemetry context managers that use nullcontext() when OTEL_ENABLED is false
• Added null checks before calling span methods to prevent errors when spans are None
• Ensured telemetry operations are properly gated behind the OTEL_ENABLED environment variable

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/flexible_inference_benchmark/main.py	Updated main experiment span creation to use conditional context manager and added null check for span attribute setting
src/flexible_inference_benchmark/engine/backend_functions.py	Modified all OpenTelemetry span creation to be conditional and added null checks for span method calls throughout the request processing

[hjjq]

Thanks!!