[config] Adopt configuration `v0.4.0`

[douglascamata]

Problem Statement

A new version of the Otel configuration has been released (see open-telemetry/opentelemetry-configuration#190) a few days ago and it brings some changes, including breaking ones, but it's a great step forward towards a better and more stable configuration.

Proposed Solution

Adopt the new configuration version and prepare all the required code around it.

[douglascamata]

Implementation happening in #7268