Two models fail integration tests but defy isolation

[ablaom]

Integration tests (contained in the new file /test/integration.tl) fail for two models in a very subtle way I have been unable to nail down after several days of trying. The models are:

AdaBoostStumpClassifier (interface package: MLJDecisionTreeInterface)
COFDetector (interface package :OutlierDetectorNeighbors)

If I run ] test MLJ the models fail, but if I manually execute the /test/integration.tl script, the models pass. I have carefully compared the two environment manifests that appear to be operating in the two cases and they are identical. I can see no trace of some RNG-related difference.

For now I have excluded the models from integration tests, with a reference to this issue in the test code.

Note that to force integration tests to run, you must set the env variable MLJ_TEST_INTEGRATION="true".