v2 sr sanity crashes when a pid file exists but the config doesn't

[reidsunderland]

I marked this v2 only, but haven't yet confirmed that sr3 handles this situation any better.

When a pid file exists in the .cache directory, but the corresponding config file has been removed, sr sanity crashes.

We're observing it on 2.21.4 but I don't see any changes in the related code, so I don't think it was fixed.

sanity: missing: [['sender', 'configname', 1]]
starting them up...
Traceback (most recent call last):
  File "/usr/bin/sr", line 11, in <module>
    load_entry_point('metpx-sarracenia==2.21.4', 'console_scripts', 'sr')()
  File "/usr/lib/python3/dist-packages/sarra/sr.py", line 1094, in main
    gs.sanity()
  File "/usr/lib/python3/dist-packages/sarra/sr.py", line 766, in sanity
    self._start_missing()
  File "/usr/lib/python3/dist-packages/sarra/sr.py", line 728, in _start_missing
    self._launch_instance(component_path, c, cfg, i)
  File "/usr/lib/python3/dist-packages/sarra/sr.py", line 90, in _launch_instance
    s = self.configs[c][cfg]['options'].statehost.lower()
KeyError: 'configname'

[reidsunderland]

I reproduced the bug on the v2_dev branch, so it wasn't fixed.

[reidsunderland]

with my fix, we get this:

sanity: missing: [['sarra', 'get_copernicus', 1]]
starting them up...
sarra get_copernicus is not a known config, cannot start it. Maybe the config file is missing?
killing strays...

$? = 0

instead of

sanity: missing: [['sarra', 'get_copernicus', 1]]
starting them up...
Traceback (most recent call last):
  File "/net/local/home/sunderlandr/.local/bin/sr", line 33, in <module>
    sys.exit(load_entry_point('metpx-sarracenia', 'console_scripts', 'sr')())
  File "/net/local/home/sunderlandr/sarra_v2/sarra/sr.py", line 1106, in main
    gs.sanity()
  File "/net/local/home/sunderlandr/sarra_v2/sarra/sr.py", line 778, in sanity
    self._start_missing()
  File "/net/local/home/sunderlandr/sarra_v2/sarra/sr.py", line 740, in _start_missing
    self._launch_instance(component_path, c, cfg, i)
  File "/net/local/home/sunderlandr/sarra_v2/sarra/sr.py", line 91, in _launch_instance
    s = self.configs[c][cfg]['options'].statehost.lower()
KeyError: 'get_copernicus'

$? = 1