chore(examples): lint examples/koa using shared top-level eslint config

[trentm]

Refs: #2891

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.81%. Comparing base (196b7a1) to head (b257485).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2903      +/-   ##
==========================================
+ Coverage   89.76%   89.81%   +0.04%     
==========================================
  Files         187      187              
  Lines        9149     9149              
  Branches     1885     1885              
==========================================
+ Hits         8213     8217       +4     
+ Misses        936      932       -4     

see 1 file with indirect coverage changes

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[trentm]

FYI: This need to eslint-disable-next-line import/extensions will be dropped once all examples/ packages are using the top-level eslint.config.js and we can delete examples/.eslintrc. It is the "extends": "airbnb-base", in "examples/.eslintrc" that is making this necessary for now.

(The alternative is to delete "examples/.eslintrc" and possibly break npm run lint:examples in the top-level until I complete all the items in #2891)

[maryliag]

do you have an issue to track dropping the comments (on this and any other PR that you had to add it) or can you update the issue 2891 to include that as a step?