Fix and Update Telemetry Properties and Tests

[armando-rodriguez-cko]

Description:

This PR significantly refactors telemetry data management in the SDK and enhances tests to ensure more efficient and reliable tracking of HTTP request metrics.

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Key Changes:

Telemetry Refactor:

• Replaced ThreadLocal<Map<String, Object>> with ThreadLocal<RequestMetrics> for a more structured telemetry data management.
• Introduced the RequestMetrics class with dedicated methods for generating and formatting telemetry headers.
• Simplified exception handling in ApacheHttpClientTransport with a centralised handleException method.

Telemetry API Enhancements:

• Telemetry headers now include:
  • prev_request_id: ID of the previous request.
  • request_id: Unique ID of the current request.
  • prev_request_duration: Duration of the previous request in milliseconds.
• Telemetry data is now formatted as clean JSON using the toTelemetryHeader method in RequestMetrics.

Extended Tests:

• Telemetry Integration Tests:
  • Validate telemetry headers for individual and concurrent requests.
  • Ensure unique headers in high-concurrency scenarios.
• Load Testing:
  • Simulated 1000 concurrent requests to evaluate the system's robustness under heavy load.

Fixes:

• Resolved code duplication in HTTP client setup.
• Removed redundant dependencies and simplified header handling.

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Impact:

• Performance: Reduced memory usage by consolidating telemetry handling into a specific class.
• Maintainability: Cleaner and modular code, facilitating future enhancements.
• Reliability: Enhanced tests ensure consistent behavior under varying conditions.

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Additional Notes:

• Changes require reviewing external dependencies interacting with ApacheHttpClientTransport.
• Some tests marked as @Disabled are available for manual testing under specific scenarios.