Deprecation: #76101 - remove SoloFieldContainer

See Issue #76101

Description

The render() method of the SoloFieldContainer class has been marked as deprecated. It is not used in core anymore.

Impact

Using the method will trigger a deprecation log entry.

Affected Installations

Instances with custom extensions that use render() from SoloFieldContainer.

Migration

Use the render method from the ListOfFieldsContainer class.