Remove the overwriting of sys.argv

[nbelakovski-mssm]

There's no need to do this since argparse can accept a list of arguments, and it doesn't seem like a good idea to overwrite the list of arguments provided.

Reference issue

N/A

Tasks

• Unit tests added that reproduce issue or prove feature is working
• Fix or feature added
• Documentation and examples updated (if relevant)
• Unit tests passing and coverage at 100% after adding fix/feature
• Type annotations updated and passing with mypy
• Apps updated and tested (if relevant)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (ca0fda1) to head (ec1aa5d).

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #961   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           28        28           
  Lines         8708      8708           
=========================================
  Hits          8708      8708           

Files	Coverage Δ
pynetdicom/__main__.py	100.00% <100.00%> (ø)

[scaramallion]

Thanks!