hdd_extents errors out and doesn't create JSON if there is no ER title after ER#

[arhonemus]

Change behavior to report no title
Traceback (most recent call last):
  File "/mnt/c/Users/foren/Documents/digarch_scripts-1/src/digarch_scripts/report/report_hdd_extents.py", line 192, in
    main()
  File "/mnt/c/Users/foren/Documents/digarch_scripts-1/src/digarch_scripts/report/report_hdd_extents.py", line 183, in main
    full_report = create_report(ers, stub_report)
  File "/mnt/c/Users/foren/Documents/digarch_scripts-1/src/digarch_scripts/report/report_hdd_extents.py", line 135, in create_report
    report = process_item(er, report)
  File "/mnt/c/Users/foren/Documents/digarch_scripts-1/src/digarch_scripts/report/report_hdd_extents.py", line 162, in process_item
    process_item(input, {'title': parent, 'children': []})
  File "/mnt/c/Users/foren/Documents/digarch_scripts-1/src/digarch_scripts/report/report_hdd_extents.py", line 162, in process_item
    process_item(input, {'title': parent, 'children': []})
  File "/mnt/c/Users/foren/Documents/digarch_scripts-1/src/digarch_scripts/report/report_hdd_extents.py", line 148, in process_item
    'er_number': parts.group(1),
AttributeError: 'NoneType' object has no attribute 'group'