Legacy _deb: Add option to specify packages to unmark

[artivis]

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[artivis]

Note: black complains about files that are not concerned by this PR.

[codecov-commenter]

Codecov Report

Merging #4026 (eda7979) into main (11aaab5) will decrease coverage by 0.06%.
The diff coverage is n/a.

❗ Current head eda7979 differs from pull request most recent head 89152e8. Consider uploading reports for the commit 89152e8 to get more accurate results

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@@            Coverage Diff             @@
##             main    #4026      +/-   ##
==========================================
- Coverage   91.75%   91.69%   -0.06%     
==========================================
  Files          79       78       -1     
  Lines        5302     5192     -110     
==========================================
- Hits         4865     4761     -104     
+ Misses        437      431       -6     

Impacted Files	Coverage Δ
snapcraft/commands/extensions.py	98.11% <0.00%> (-1.89%)	⬇️
snapcraft/elf/elf_utils.py	93.65% <0.00%> (-1.74%)	⬇️
snapcraft/commands/discovery.py	90.69% <0.00%> (-0.80%)	⬇️
snapcraft/extensions/registry.py	90.00% <0.00%> (-0.48%)	⬇️
snapcraft/utils.py	91.42% <0.00%> (-0.05%)	⬇️
snapcraft/elf/_elf_file.py	97.21% <0.00%> (ø)
snapcraft/linters/linters.py	97.59% <0.00%> (ø)
snapcraft/parts/lifecycle.py	88.58% <0.00%> (ø)
snapcraft/extensions/kde_neon.py
snapcraft/linters/library_linter.py	87.23% <0.00%> (+1.15%)	⬆️

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