processes in the handling dict in the job conf dict is a dict, not a list

[natefoo]

Should fix the test error in galaxyproject/galaxy#13995:

Traceback (most recent call last):
1056
  File "/home/runner/work/galaxy/galaxy/galaxy root/.venv/lib/python3.7/site-packages/gravity/commands/cmd_register.py", line 18, in cli
1057
    cm.add(config)
1058
  File "/home/runner/work/galaxy/galaxy/galaxy root/.venv/lib/python3.7/site-packages/gravity/config_manager.py", line 418, in add
1059
    conf = self.get_config(config_file, defaults=defaults)
1060
  File "/home/runner/work/galaxy/galaxy/galaxy root/.venv/lib/python3.7/site-packages/gravity/config_manager.py", line 143, in get_config
1061
    for service_name in [x["service_name"] for x in ConfigManager.get_job_config(job_config) if x["service_name"] not in webapp_service_names]:
1062
  File "/home/runner/work/galaxy/galaxy/galaxy root/.venv/lib/python3.7/site-packages/gravity/config_manager.py", line 212, in get_job_config
1063
    for handler_name, handler_options in processes.items():
1064
AttributeError: 'list' object has no attribute 'items'