Fix manifest files for checkbox-ng and checkbox-support (infra)

[pieqq]

snap_utils is still part of checkbox_support for the time being, so the test files are also still located there.

Description

Resolved issues

Documentation

Tests

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 57.66%. Comparing base (e806296) to head (7cf08fc).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2379   +/-   ##
=======================================
  Coverage   57.66%   57.66%           
=======================================
  Files         465      465           
  Lines       47166    47166           
  Branches     8398     8398           
=======================================
  Hits        27198    27198           
+ Misses      19085    19084    -1     
- Partials      883      884    +1     

Flag	Coverage Δ
checkbox-ng	75.60% <ø> (ø)
checkbox-support	66.64% <ø> (ø)

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