Remove trace logging from ML datafeeds in tests
Remove trace logging from ML datafeeds in tests

This was added to investigate a test failure over two years ago, yet
left behind. Since the test failure has been addressed since then, this
commit removes the trace logging.

strapdata/elassandra,strapdata/elassandra,strapdata/elassandra,strapdata/elassandra,vroyer/elassandra,vroyer/elassandra,vroyer/elassandra,strapdata/elassandra