Improve concatenation with drivers

[bruno-at-orange]

Description

In most of the parallel tasks, slaves produce files (called chunk) that must be concatenated to produce a final file. The concatenation process basically consists of:

• Each chunk file is sent to the master via MPI
• The master writes/appends the received chunk to the result file

Questions/Ideas

• Use drivers for concatenation:
  • Each slave writes directly to the cloud
  • We call a new method form the drivers dedicated to concatenation. It should be more efficient than the write/append that is not very cloud native.
• Another solution would be to write chunks directly to the cloud as part of a multipart file

[lucaurelien]

@bruno-at-orange to define the API Tristan to implement in the Azure Driver + to bench the impact // @bruno-at-orange to implement it in khiops-core

[lucaurelien]

regarder : #778