Typing: Fix pyright type issues in apt module

[ByteOtter]

What this PR does / why we need it:

This PR is the first of a series that fixes all issues raised by pyright.
In this case, it fixes smaller typing issues within the apt module that are caused by inaccurate function signatures not reflecting possible None values.

It does not change the underlying logic, but adjusts the function signatures to reflect the types correctly.

Which issue(s) this PR fixes:
Tracks #152

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.23%. Comparing base (76dcb4e) to head (8cf0fa2).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #201   +/-   ##
=======================================
  Coverage   93.23%   93.23%           
=======================================
  Files          30       30           
  Lines        1375     1375           
=======================================
  Hits         1282     1282           
  Misses         93       93           

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[NotTheEvilOne]

LGTM