[Python] Add OpenTelemetry integration in multi-server sample

## Description

Need to add OpenTelemetry integration to the multi-server sample.

## Location
- File: `py/samples/multi-server/src/main.py`
- Line: 62
- Current code: `# TODO: Add opentelemetry integration`

## Acceptance Criteria
- [ ] Integrate OpenTelemetry with multi-server sample
- [ ] Add proper tracing and metrics