More strictly check against unexpected arguments in policy

[marmarta]

fixes QubesOS/qubes-issues#8525

[codecov]

Codecov Report

Merging #173 (828b489) into main (2fd4eec) will decrease coverage by 0.07%.
The diff coverage is 83.87%.

@@            Coverage Diff             @@
##             main     #173      +/-   ##
==========================================
- Coverage   95.86%   95.79%   -0.07%     
==========================================
  Files          43       43              
  Lines        8343     8371      +28     
==========================================
+ Hits         7998     8019      +21     
- Misses        345      352       +7     

Files	Coverage Δ
qubes_config/tests/test_policy_rules.py	100.00% <100.00%> (ø)
qubes_config/global_config/policy_rules.py	93.68% <88.88%> (+0.13%)	⬆️
qubes_config/global_config/usb_devices.py	92.22% <33.33%> (-1.00%)	⬇️

... and 2 files with indirect coverage changes