refac: structure of test/workloads folder that makes more sense

test/conftest.py

test/helper.py

test/schedconf/dm_user_degrad.json

test/schedconf/dm_user_delay.json

test/schedconf/dm_user_delay_w_log.json

test/schedconf/dm_user_reconfig.json

test/schedconf/dm_user_renonce.json

test/schedconf/reconfig_alpha.json

test/schedconf/replay_user_reconfig.json

test/schedconf/replay_user_rigid.json

test/test_algo_perso.py

test/test_broker.py

test/test_dm_users.py

test/test_fb_users.py

test/test_runner.py

test/test_users.py

test/workloads/dyn/MC_minos_trunc.json

test/workloads/dyn/two_jobs.json

test/workloads/dyn/user10.json

test/workloads/dyn/user11.json