feat: As a user, I want to be added in default log-format the consumer_group_id variable

[felpasl]

Description

I need to include a consumer_group_id in the default log variables or have an option to add extra variables to an existing log.

I understand we have log_format, but it is going to take too long, and I need the full log information. Creating this will result in a huge template and a complex plugin configuration.