Convention based tests groups are not properly interpreted

[fiedukow]

Groups listed in convention based tests are not read properly. It can be reproduced in presto-product-tests by excluding (for example) tpcds group. TPCDS convention based tests are still started (and all of them all failing). It is visible that tempto logs groups of those tests to be empty.

[kokosing]

Maybe you could try to fix this once you are playing around?