Set to Header only Headers

[s1lver]

I`m setting headers and properties

If i use function $message->getHeaders() i get properties instead and if use $message->getProperties() i get headers!!!

This PR fixing it

Before fix

{"headers":{"delivery_mode":1,"user_id":"guest"}}

After fix

{"headers":{"traceparent":"00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01","z-traceparent":"dsjdhsjdhsjds"}}

[makasim]

This would be a huge BC break. There are a lot of projects which rely on current behavior, even though it's not correct.

[s1lver]

This would be a huge BC break. There are a lot of projects which rely on current behavior, even though it's not correct.

Maybe add a description to UPGRADE.md?

[makasim]

That would require a version bump and a lot of work on my side. I'd prefer to avoid it.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.