Include group in check metrics

[olegbespalov]

Feature Description

Currently metrics for checks are generated as k6.check.expected_Expect_HttpStatus_to_equal_201.pass

It would be great if metrics include the group e.g.

k6.check.group_create_customer.expected_Expect_HttpStatus_to_equal_201.pass

Ideally should also support nested groups e.g.

• Onboard customer journey
  - Submit Identity Card
  - Register Password
  - Accept T&C

Suggested Solution (optional)

Given this is a breaking change for existing dashboards or consumers of these metrics, would probably need to put it behind some feature flag/configuration.

Already existing or connected issues / PRs (optional)

The issue ported from the grafana/k6#2980