Fix validate plugin command line

[jmthomas]

Broken by #1707 refactor

[codecov]

Codecov Report

Merging #1727 (ab8c6f5) into master (5196c49) will increase coverage by 0.00%.
The diff coverage is n/a.

❗ Current head ab8c6f5 differs from pull request most recent head 3f1e2a6. Consider uploading reports for the commit 3f1e2a6 to get more accurate results

@@           Coverage Diff           @@
##           master    #1727   +/-   ##
=======================================
  Coverage   78.17%   78.17%           
=======================================
  Files         236      236           
  Lines       18252    18253    +1     
=======================================
+ Hits        14268    14269    +1     
  Misses       3984     3984           

Impacted Files	Coverage Δ
lib/cosmos/models/plugin_model.rb	88.81% <0.00%> (+0.07%)	⬆️

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