remove unused test stubs

[hippalectryon-0]

Requires #424

Removed unused ./test-packages

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.21%. Comparing base (277a03a) to head (ea5325c).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #431      +/-   ##
==========================================
+ Coverage   76.20%   76.21%   +0.01%     
==========================================
  Files          53       53              
  Lines        9359     9359              
==========================================
+ Hits         7132     7133       +1     
+ Misses       2227     2226       -1     

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[marmarek]

Hm, it used to be used by pylint to check some of the external modules not directly available in the CI env. I see CI passed - does pylint now ignore external modules? I don't see qubesdb on the ignored-modules list and also I'm pretty sure it isn't installed in the CI env. What changed?
dbus stub indeed seems not used anymore.

[hippalectryon-0]

What changed?

I don't remember making any intentional changes to that effect - I suppose it's been that way for some time now ?