example/dice: Use resource.NewSchemaless instead of resource.NewWithAttributes

[pellared]

Why

See: open-telemetry/opentelemetry.io#3838 (comment)

What

Use resource.NewSchemaless instead of resource.NewWithAttributes to mitigate the "resource merge conflict" runtime error that the users encounter have when bumping OTel Go when they are using the existing "getting started" example (https://opentelemetry.io/docs/languages/go/getting-started/#initialize-the-opentelemetry-sdk).

Related to #2341

[dmathieu]

With this change, we will likely end up with most users not using the schema version. Is that the signal we want to provide?
Should there be a documentation section explaining both and the pros/cons of each, so we could link to it?

[pellared]

Should there be a documentation section explaining both and the pros/cons of each, so we could link to it?

That may be good especially until we have something like #4503 (which I do not expect to happen soon).

How about doing it in a separate PR? Are you willing to help with it?

[MrAlias]

With this change, we will likely end up with most users not using the schema version. Is that the signal we want to provide?

Right, I agree that is not the message we want to send users. I think this takes a step in the wrong direction.

[pellared]

I have a different idea. I think we can just use resource.Default() and set OTEL_SERVICE_NAME and OTEL_RESOURCE_ATTRIBUTES here: https://opentelemetry.io/docs/languages/go/getting-started/#run-the-application.

I will create a separate PR later this week. Changing this one to draft.