build(snap): Upgrade snap base to core22, remove deprecated plug

[MonicaisHer]

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PR Checklist

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• [x] I am not introducing a breaking change (if you are, flag in conventional commit message with BREAKING CHANGE: describing the break)
• [x] I am not introducing a new dependency (add notes below if you are)
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[codecov-commenter]

Codecov Report

Merging #294 (bc6e96f) into main (7429475) will not change coverage. The diff coverage is n/a.

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@@          Coverage Diff          @@
##            main    #294   +/-   ##
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  Coverage   0.00%   0.00%           
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  Files          2       2           
  Lines        222     222           
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  Misses       222     222           

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