Currently, the CQF feature flag (featureFlagCommonQueryFramework) is marked as always-disabled, so we don't get CQF coverage by default on the all-feature-flags variants. One reason we wanted to wait on taking the CQF FF off the always-disabled list is that, once enabled, it would take precedence over the SBE feature flag (featureFlagSbeFull), reducing coverage of the SBE stage builders. 

To get some additional coverage, in SERVER-66954 we introduced a new variant with a select list of tasks to run with the CQF feature flag enabled manually. This was intended to be a temporary measure; this ticket tracks deleting the new variant.