dataset header causes warning in console

[JamieDanielson]

Versions

main as of commit 55dddd3

Steps to reproduce

1. add API key and run example
2. see warning in console "http-json-trace-exporter.js:16 Header "x-honeycomb-dataset" has wrong value and will be ignored"

Additional context

dataset header should only get set if needed. looks like we set the header key in the exporter, and leave the value undefined if not classic... but even without a value the key is there so we get a console warning.

This is a nuisance issue, not a big deal but should be updated

[JamieDanielson]

Never mind I think I had an old version at the time, this isn't a current issue.

[JamieDanielson]

Reopening, I think there's still an issue here