SkipScan plan not chosen when only 1 chunk remains

[svenklemm]

When using DISTINCT queries that would result in SkipScan being used the plan including SkipScan will not be picked when only 1 chunk remains in the query plan.

We do get the correct plan when querying the chunk directly but not when querying through the hypertable with query constraints resulting in exclusion of all but 1 chunk.