Issue #13968: Fixed newly added recursive glob test.
It was failed when run with non-empty current directory.
Closes #22336: attemptckalloc() with PyMem_Malloc() in _tkinter

The PyMem_Malloc(size) function has a well defined behaviour: if size is 0, a
pointer different than NULL is returned. PyMem_Malloc() allocations are
tracked by tracemalloc, attemptckalloc() allocations are not tracked.