src: remove unused variables from report

[iknoom]

This PR removes unused variables in node_report.cc detected by clang-tidy(bugprone-unused-local-non-trivial-variable).

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.46%. Comparing base (cff138c) to head (bb421bb).
⚠️ Report is 27 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #60047   +/-   ##
=======================================
  Coverage   88.45%   88.46%           
=======================================
  Files         703      703           
  Lines      207546   207544    -2     
  Branches    40016    40011    -5     
=======================================
+ Hits       183595   183598    +3     
+ Misses      15956    15942   -14     
- Partials     7995     8004    +9     

Files with missing lines	Coverage Δ
src/node_report.cc	93.14% <ø> (-0.03%)	⬇️

... and 38 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/69407/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/69411/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/69414/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/69459/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/69468/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/69503/