FR-5570 - Support the keep-enabled parameter in ubuntu-image extra-ppas

[upils]

To use newly testing object this PR is rebased on https://github.com/canonical/ubuntu-image/tree/add-pack-feature.

[codecov]

Codecov Report

Merging #150 (0e6e016) into main (73ec099) will decrease coverage by 0.10%.
Report is 2 commits behind head on main.
The diff coverage is 95.90%.

❗ Current head 0e6e016 differs from pull request most recent head 9cca2e6. Consider uploading reports for the commit 9cca2e6 to get more accurate results

@@            Coverage Diff             @@
##             main     #150      +/-   ##
==========================================
- Coverage   90.58%   90.48%   -0.10%     
==========================================
  Files          13       13              
  Lines        2516     2533      +17     
==========================================
+ Hits         2279     2292      +13     
- Misses        210      214       +4     
  Partials       27       27              

Files	Coverage Δ
internal/statemachine/classic_states.go	97.31% <100.00%> (+0.03%)	⬆️
internal/statemachine/helper.go	98.67% <100.00%> (+0.01%)	⬆️
internal/statemachine/pack.go	100.00% <100.00%> (ø)
internal/statemachine/pack_states.go	100.00% <100.00%> (ø)
internal/statemachine/state_machine.go	98.00% <ø> (-0.03%)	⬇️
cmd/ubuntu-image/main.go	91.50% <97.36%> (-0.46%)	⬇️
internal/statemachine/common_states.go	99.08% <95.23%> (-0.02%)	⬇️
internal/helper/helper.go	35.58% <0.00%> (-0.52%)	⬇️

... and 1 file with indirect coverage changes

[sil2100]

Generally +1 on the changes, good test coverage. Changes themselves solid and that's the way to go. Included two small changes, but nothing too critical.

[sil2100]

Looks good! I'll bump the version and changelog and then merge (after tests finish running).