Fix routine when a stationxml is not present although a related mseed exists

Sentry Issue: WAVEQC-V

FileNotFoundError: [Errno 2] No such file or directory: '/tmp/waveqc/stations/RA_OGLP.xml'
(2 additional frame(s) were not displayed)
...
  File "waveqc/tasks.py", line 203, in check_item
    result = check_removable_response(stream, channel, network, station, count)
  File "waveqc/tasks.py", line 171, in check_removable_response
    inventory = read_inventory(

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information