TestAskWithGapsEnabled still uses reasonerEnabled instead of reasonerLevel

[bnouwt]

Somehow this REST test (in module smart-connector-rest-dist) succeeds despite still using the deprecated reasonerEnabled property instead of the newer reasonerLevel property.

Change to reasonerLevel (probably needs level 4) and check whether the knowledge gaps actually function properly.

[bnouwt]

Note that @DaviddeBest-TNO fixed the incorrect property in PR #723, but reasonerLevel=2 should not be enough to find knowledge gaps, but somehow it does. Very strange.