Add Input/Output Events to OpenTelemetry Spans in PromptFlow

[liucheng-ms]

Description

This pull request introduces changes to the tracing functionality in PromptFlow. Specifically, it adds input and output events to the OpenTelemetry spans. The event names are promptflow.function.inputs and promptflow.function.output, and their attributes contain a payload which is a JSON dump of the input/output values. This enhancement will provide more detailed tracing information and facilitate debugging and performance monitoring.

This PR also includes updates to the relevant unit tests to validate these new events and their payloads.

All Promptflow Contribution checklist:

• The pull request does not introduce [breaking changes].
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.
• Create an issue and link to the pull request to get dedicated review from promptflow team. Learn more: suggested workflow.

General Guidelines and Best Practices

• Title of the pull request is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.

[github-actions]

promptflow-tracing test result

 12 files   12 suites   3m 45s ⏱️
  9 tests   9 ✅ 0 💤 0 ❌
108 runs  108 ✅ 0 💤 0 ❌

Results for commit 5134767.

♻️ This comment has been updated with latest results.

[github-actions]

promptflow SDK CLI Azure E2E Test Result liucheng/20240326_span_event

  4 files    4 suites   5m 28s ⏱️
196 tests 176 ✅ 20 💤 0 ❌
784 runs  704 ✅ 80 💤 0 ❌

Results for commit 5134767.

♻️ This comment has been updated with latest results.

[github-actions]

Executor E2E Test Result liucheng/20240326_span_event

217 tests   215 ✅  5m 8s ⏱️
  1 suites    2 💤
  1 files      0 ❌

Results for commit 5134767.

♻️ This comment has been updated with latest results.

[github-actions]

SDK CLI Test Result liucheng/20240326_span_event

   12 files     12 suites   49m 4s ⏱️
  499 tests   480 ✅ 19 💤 0 ❌
1 996 runs  1 920 ✅ 76 💤 0 ❌

Results for commit 5134767.

♻️ This comment has been updated with latest results.