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.

[bnouwt]

After inspecting this unit test more closely it is not strange at all that it returns knowledge gaps despite only having reasonerLevel of 2, because whenever a KI is registered with knowledge gaps enabled, @JackJackie made sure using this code that the match strategy (i.e. reasoner level) is high enough.

This unit test also prints:

The MatchStrategy should be 'SUPREME_LEVEL' when Knowledge Gaps are enabled. Overriding default.

to indicate this.