Currently `npm test` runs the Cucumber suite with a matrix
configuration for selecting the algorithm (CH, MLD) and data loading
(shared-memory, mmap) options.
However, there is a third data loading option, 'load directly',
which is to directly load the datasets into the osrm-routed process memory.
The code paths for each data loading option are distinct:
Storage::Run + SharedMemoryAllocator
MMapMemoryAllocator
ProcessMemoryAllocator
This commit adds direct data loading as part of the Cucumber
configuration matrix.
This will ensure optional dataset support can be added without any
regressions.