Introduce beta API as experimental feature

[a-thaler]

Description

As part of #767 introduce a new beta API for the telemetry module, running behind a feature flag for now and being available via the development release only.

Criterias

• In the development release a new beta version is available having the exact same syntax for now
• The controller should be based on the new version (which is the stored one) behind a feature flag active in development release
• A small test suite for the development release is testing already against the new beta version, for now the existing test suites stay as they are

Reasons

Attachments

Release Notes