chore(eslint): lint examples/bunyan and prepare for linting .js and .mjs files

[trentm]

This adds support for 'npm run lint' in examples/bunyan, using the same
base eslint.config.js used by most of the repo.

There are ulterior motives:

• This is a first step to linting all the examples using the same
  base config (rather than the spotty linting of examples using the
  separate "examples/.eslintrc".
• The eslint.config.js changes support being used to lint .ts,
  .js, and .mjs files reasonably. I'll follow-up with a separate PR
  adding linting of .mjs files used for some ESM testing. (coordinate linting of JS files in examples/* and .mjs files in the repo #2891 for the follow-up.)
  (e.g. "instrumentation-ioredis/test/fixtures/use-ioredis.mjs")
• I'll follow-up separately to get 'npm run lint' working for
  other examples and get the top-level npm run lint:examples
  using those. (coordinate linting of JS files in examples/* and .mjs files in the repo #2891 for the follow-up.)

Hattip to the following for some of the eslint config changes:
https://github.com/open-telemetry/opentelemetry-js/pull/4446/files#diff-1a88e8e72db982c999acf146817a416a02d93547458e6525610cf69b24751af9

---

If it helps review:

• the first commit is just the config changes
• the second commit is the changes to examples/bunyan to get 'npm run lint' passing

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.76%. Comparing base (5909ad4) to head (607a383).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2567      +/-   ##
==========================================
+ Coverage   89.53%   89.76%   +0.23%     
==========================================
  Files         182      187       +5     
  Lines        8837     9147     +310     
  Branches     1844     1884      +40     
==========================================
+ Hits         7912     8211     +299     
- Misses        925      936      +11     

see 6 files with indirect coverage changes

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• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
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[legendecas]

Should examples/bunyan be added to the package.json#workspaces list in order to run linter on CI regularly?

opentelemetry-js-contrib/package.json

Lines 79 to 86 in 8bfa21f

	"workspaces": [
	"packages/*",
	"plugins/node/*",
	"plugins/web/*",
	"propagators/*",
	"detectors/node/*",
	"metapackages/*"
	]

[trentm]

Should examples/bunyan be added to the package.json#workspaces list in order to run linter on CI regularly?

I was initially thinking no. Instead I was going to consider adding a lint:examples script to the set of npm run lint things. The last I recall we took the examples out of the workspace to help with shared package-lock deps, because the examples were so behind.

[JamieDanielson]

I was going to consider adding a lint:examples script to the set of npm run lint things.

I like this idea. It's super useful to have linters run against examples but shouldn't block any other builds. I would love to have proper linting on all the examples.

[JamieDanielson]

we took the examples out of the workspace to help with shared package-lock deps, because the examples were so behind.

That's right. Similarly to my comment before, while it's useful to have CI run on examples regularly, if they are not being kept up to date, we don't want to have problems with the packages themselves. We need to revisit our examples strategy in general though to ensure they are useful while also not hindering forward progress.

[dyladan]

This has a conflict but I think it can be merged after that