Fix: Add workflow name to telemetry resource attributes

[cocosheng-g]

This PR adds the workflow name to the OpenTelemetry resource attributes in the collector configuration. This fixes the issue where GEMINI_CLI_WORKFLOW_NAME is null in metric events for customer-triggered runs. Closes #492

[gemini-cli]

🤖 Hi @cocosheng-g, I've received your request, and I'm working on it now! You can track my progress in the logs for more details.

[gemini-cli]

📋 Review Summary

This PR correctly adds the workflow name to the OpenTelemetry resource attributes in the collector configuration. This ensures that telemetry events contain the workflow context, effectively fixing the issue where it was previously missing or null in customer-triggered runs.

🔍 General Feedback

• The addition is well-integrated and consistent with existing resource attribute patterns in the configuration template.
• Leveraging the sanitize_workflow_name step is a good practice, ensuring that the workflow name is safe for shell command expansion and formatted correctly for telemetry purposes.
• The use of GH_WORKFLOW_NAME across multiple steps in action.yml remains consistent with the local conventions of this project.