refactor(instrumentation-mysql2): improve performance of getSpanName using substring

[geotry]

Which problem is this PR solving?

We noticed that getSpanName() from instrumentation-mysql2 was taking non-negligeable time from our profiler in production, considering that it's in a critical path.

This PR replaces split() by substring() to avoid instanciating a new array everytime.

Here is a benchmark with the difference before and after (~20 times faster for me): https://jsbm.dev/YtumA6nRNvjVJ

Short description of the changes

Use substring() with indexOf() instead of split() to extract the SQL verb from a sql query. It also checks for queries with no spaces like "COMMIT" and fallback to return the raw query.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: geotry / name: Geoffrey Thierry (ddd8401, aed3839, d0fae7c)
• ✅ login: david-luna / name: David Luna (868ed59, 07a9d46)

[maryliag]

Would you mind doing the same change on the other mysql package, to keep consistency: https://github.com/open-telemetry/opentelemetry-js-contrib/blob/main/plugins/node/opentelemetry-instrumentation-mysql/src/utils.ts#L118

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 77.77778% with 2 lines in your changes missing coverage. Please review.

Project coverage is 90.86%. Comparing base (d056d21) to head (07a9d46).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...e/opentelemetry-instrumentation-mysql/src/utils.ts	80.00%	1 Missing ⚠️
.../opentelemetry-instrumentation-mysql2/src/utils.ts	75.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2470      +/-   ##
==========================================
- Coverage   90.88%   90.86%   -0.02%     
==========================================
  Files         159      159              
  Lines        7844     7849       +5     
  Branches     1616     1621       +5     
==========================================
+ Hits         7129     7132       +3     
- Misses        715      717       +2     

Files with missing lines	Coverage Δ
...e/opentelemetry-instrumentation-mysql/src/utils.ts	95.65% <80.00%> (-2.08%)	⬇️
.../opentelemetry-instrumentation-mysql2/src/utils.ts	94.44% <75.00%> (-2.53%)	⬇️

[david-luna]

@geotry

Thanks for contributing to OpenTelemetry :)

Could you run npm run lint:fix and push the changes to pass all checks?

[geotry]

thanks for the review

@maryliag I implemented the change in instrumentation-mysql, but it was slightly different as it was returning the full query string in case of an object instead of just the verb. I'm not sure wether it's safe or not to apply this change as a test was failing.

I also fixed the lint issues, sorry about that @david-luna

[maryliag]

Thank you for updating the other package too! 😄
I'm waiting for a maintainer to approve the workflows so we can see what is failing and get a fix for it, then we can get this merged