[sdk-logs] remove env var configuration from `@opentelemetry/sdk-logs`

[pichlermarc]

Description

Note

Not yet ready for implementation. Needs to decision where the config code should go.

In the Metrics SDK, we don't include any env-var configuration OOTB, one has to use @opentelemetry/sdk-node to get env var config. We should do the same with the Logs SDK while it's still experimental (eventually also the Trace SDK) to properly separate the SDK functionality and configuration concerns early on.

This issue is considered done when:

• any env var configuration for @opentelemetry/sdk-logs has been moved to @opentelemetry/sdk-node or @opentelemetry/configuration