Add message when multiple datasets are requested and return_vars has common dimensions

See merge request !222

Correct dat name of work_pieces (internal usage only); Add message when multiple datasets are requested and return_vars has common dimensions

Suppress message of all unit tests

See merge request !221

Suppress message of all unit tests because testthat edition 3 shows the messages. Run unit test on GitLab.

Add run_dir document; add Autosubmit use case

See merge request !219

Develop v2.3.0

See merge request !217

Autosubmit as workflow manager

See merge request !215

Allow selectors to be integer

See merge request !216

Change autosubmit 'THREADS' back  to 'cores_per_job'; Modify documentation about ncores and num_procs