feat(#168): optimized rultor build

[h1alexbel]

In this pull, I've optimized rultor build for both: release and merge, removed redundant command executions in release section.

ref #168

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PR-Codex overview

This PR focuses on updating the build process in the GitHub Actions workflow and the justfile. It modifies the installation steps and code generation commands, streamlining the process and removing unnecessary npm commands.

Detailed summary

• Updated run commands in .github/workflows/codecov.yml to include just install before just gen.
• Removed npm --version checks and installation of @openapitools/openapi-generator-cli from the gen and rultor sections.
• Replaced npm install with just gen in the rultor section.
• Added export RULTOR=true in the merge section.
• Simplified the gen command to use ${RULTOR:+sudo} for conditional sudo.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.15%. Comparing base (af11195) to head (e81b1dc).
Report is 3 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #180   +/-   ##
=======================================
  Coverage   83.15%   83.15%           
=======================================
  Files          16       16           
  Lines         285      285           
=======================================
  Hits          237      237           
  Misses         48       48           

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[0crat]

@h1alexbel Thanks for your contribution! Your reward is +4 points, calculated as follows: +4 base, -16 for no code review, -4 for insufficient comments (only 1), and +20 to meet the minimum. While this isn't ideal, remember that quality and speed are both crucial. For future contributions, ensure you get a code review and encourage more comments to maximize your points. Your current balance stands at +51. Keep up the good work!