chore: add otel headers config to support axiom

[lrnt]

🖤

What does this PR do?

Add the ability to set authentication headers for the traces and logs OpenTelemetry endpoints.

Context: Axiom works out of the box with the otel package from uninbox but requires 2 additional headers to be set. See Axiom documentation here.

How to test:

1. Create a free Axiom account
2. Create a dataset in Axiom
3. Create an API token in Axiom
4. Change or add the following lines in .env.local. Be sure to set your API token in the Authorization header and your dataset name in the X-Axiom-Dataset header.

OTEL_ENABLED=true
OTEL_EXPORTER_TRACES_ENDPOINT="https://api.axiom.co/v1/traces"
OTEL_EXPORTER_TRACES_HEADERS="{"Authorization": "Bearer ***AXIOM-API-KEY***", "X-Axiom-Dataset": "***AXIOM-DATASET***"}"
OTEL_EXPORTER_LOGS_ENDPOINT="https://api.axiom.co/v1/logs"
OTEL_EXPORTER_LOGS_HEADERS="{"Authorization": "Bearer ***AXIOM-API-KEY***", "X-Axiom-Dataset": "***AXIOM-DATASET***"}"

Screenshot from a trace in Axiom:

Type of change

• Bug fix (non-breaking change which fixes an issue)
• Chore (refactoring code, technical debt, workflow improvements)
• Enhancement (small improvements)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist

Required

• Read Contributing Guide
• Self-reviewed my own code
• Tested my code in a local environment
• Commented on my code in hard-to-understand areas
• Checked for warnings, there are none
• Removed all console.logs
• Merged the latest changes from main onto my branch with git pull origin main
• My changes don't cause any responsiveness issues

Appreciated

• If a UI change was made: Added a screen recording or screenshots to this PR
• Updated the UnInbox Docs if changes were necessary

[CLAassistant]

All committers have signed the CLA.

[McPizza0]

@lrnt