Use diracx-api jobs.py module to interact with the sandbox store endpoint (instead of the one from DIRAC)

[aldbr]

Here we have a class that mimic the DIRAC SandboxStoreClient:

• mock: https://github.com/aldbr/dirac-cwl-proto/blob/a1900b590012ae03541dd90267298d4e5ba3c6d0/src/dirac_cwl_proto/data_management_mocks/sandbox.py
• real: https://github.com/DIRACGrid/DIRAC/blob/bdcf074c302c78ec06101864b7eee27a50015a36/src/DIRAC/WorkloadManagementSystem/Client/SandboxStoreClient.py

The sandbox management is already supported within diracX and should be preferred:

• https://github.com/DIRACGrid/diracx/blob/321e409fc3b0d24fd6534e38a47063b95407dabf/diracx-api/src/diracx/api/jobs.py

Tasks

• Replace the sandbox_store_client by calls diracx-api.jobs
• Replace the mock sandbox_store_client for local execution by a fake diracx-api.jobs module
• If anything is missing in diracx, let's first discuss and see if we should try to integrate it to diracx (probably just adding the assignment of the sandbox to diracx-api)

Done criteria

• existing tests should still pass