Until PM-1965-Milestone-1 will be completed, the new DDL operations implementations won't be resilient to shutdown/stepdown and concurrent workloads. So we need to introduced a new feature flag that will prevent the concurrency and step-down suites to run incompleted DDL operations.

The idea is that we will have two feature flags:
 - featureFlagShardingDDLSupport - featureFlagDisableIncompleteShardingDDLSupport

ShardingDDLSupport flag will be enable for all the "all feature flags" variants, while the DisableIncompleteShardingDDLSupport flag will be enable in all the shutdown/stepdown suites.

The new DDL operation's paths will be executed in the code only if:
(featureFlagShardingDDLSupport && !featureFlagDisableIncompleteShardingDDLSupport)

So probably we need also to introduce a wrapper to hide this complexity around the featureFlag/FCV check.