I use golang cucumber to write some tests for my application. I need clean the test data at beginning of each test feature. I call Drop and DeleteMany to clean the data of the previous test cases. But I found the Drop or DeleteMany seems not return in sync and sometimes it may impact the ongoing test, i.e., I create a doc in collection during the test but can’t find the doc in the next step. I suspect the Drop or DeleteMany do their staff during my testing running. Can someone help to clarify if the Drop or DeleteMany are async or sync function?