Bug: Use of --job option and Slurm with -x results in code error rather than extended debug output.

[jkwmoore]

Bug description:

Use of --job option and Slurm with -x results in code error rather than extended debug output.

How to reproduce:

Dispatch an installation using Easybuild's --job and -x options with the Slurm backend and observe. Not really sure what the issue might be (output suggests version parsing related?) but the error output should be of the form:

== 2023-10-25 10:48:26,855 filetools.py:526 INFO Command sbatch found at /usr/bin/sbatch
== 2023-10-25 10:48:26,855 filetools.py:526 INFO Command scontrol found at /usr/bin/scontrol
== 2023-10-25 10:48:26,855 run.py:185 INFO Auto-enabling streaming output of 'sbatch --version' command because logging to stdout is enabled
== (streaming) output for command 'sbatch --version':
  running command "sbatch --version"
  (in /users/user/new-apps-area-Easybuild-build-dir/tmp-easystack)
== 2023-10-25 10:48:26,856 slurm.py:83 INFO Found Slurm version 
Traceback (most recent call last):
  File "/usr/lib64/python3.6/runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib64/python3.6/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/main.py", line 756, in <module>
    main(prepared_cfg_data=(init_session_state, eb_go, cfg_settings))
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/main.py", line 717, in main
    hooks, do_build)
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/main.py", line 539, in process_eb_args
    submit_jobs(ordered_ecs, eb_go.generate_cmd_line(), testing=testing)
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/tools/parallelbuild.py", line 158, in submit_jobs
    return build_easyconfigs_in_parallel(command, ordered_ecs, prepare_first=prepare_first)
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/tools/parallelbuild.py", line 75, in build_easyconfigs_in_parallel
    active_job_backend = job_backend()
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/tools/job/backend.py", line 119, in job_backend
    return job_backend_class()
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/tools/job/slurm.py", line 63, in __init__
    super(Slurm, self).__init__(*args, **kwargs)
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/tools/job/backend.py", line 47, in __init__
    self._check_version()
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/tools/job/slurm.py", line 85, in _check_version
    if LooseVersion(slurm_ver) < LooseVersion(self.REQ_VERSION):
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/tools/loose_version.py", line 85, in __lt__
    return self._cmp(other) < 0
  File "/opt/apps/tuos/common/easybuild/EasyBuild/4.8.1/lib/python3.6/site-packages/easybuild/tools/loose_version.py", line 69, in _cmp
    for i, j in zip_longest(self.version, other.version, fillvalue=''):
TypeError: zip_longest argument #1 must support iteration