testing: add new test for logLevels

[jsjoeio]

This adds a test to ensure that setting the log level with process.env.LOG_LEVEL to error sets it as expected.

Fixes #4916

[codecov]

Codecov Report

Merging #4953 (04b7239) into main (3c6f85c) will increase coverage by 0.23%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #4953      +/-   ##
==========================================
+ Coverage   70.30%   70.54%   +0.23%     
==========================================
  Files          29       29              
  Lines        1677     1677              
  Branches      371      371              
==========================================
+ Hits         1179     1183       +4     
+ Misses        424      420       -4     
  Partials       74       74              

Impacted Files	Coverage Δ
src/node/cli.ts	85.87% <0.00%> (+1.52%)	⬆️

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[github-actions]

✨ Coder.com for PR #4953 deployed! It will be updated on every commit.

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