Improve running docker container parsing

[JSCU-CNI]

This PR improves the parsing of running docker containers. We've added a regression test to make sure this stays fixed.

[codecov]

Codecov Report

Attention: Patch coverage is 56.75676% with 16 lines in your changes missing coverage. Please review.

Project coverage is 76.16%. Comparing base (8387c15) to head (f54c520).

Files with missing lines	Patch %	Lines
dissect/target/plugins/apps/container/docker.py	56.75%	16 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #853      +/-   ##
==========================================
- Coverage   76.19%   76.16%   -0.03%     
==========================================
  Files         310      310              
  Lines       26674    26688      +14     
==========================================
+ Hits        20323    20328       +5     
- Misses       6351     6360       +9     

Flag	Coverage Δ
unittests	76.16% <56.75%> (-0.03%)	⬇️

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