fix(opentelemetry-resources): remove extraneous identity utils

[Delapouite]

Which problem is this PR solving?

Hi.

While skimming through the codebase in my IDE, I stumbled this identity function that has no reference. I've grepped the package to ensure this was indeed not used anymore and it's now dead code.

It was introduced in this commit but never actually used 595d0e9

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• Followed the style guidelines of this project
• Unit tests have been added
• Documentation has been updated

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.41%. Comparing base (bc9e37f) to head (6dab271).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6195   +/-   ##
=======================================
  Coverage   95.40%   95.41%           
=======================================
  Files         317      317           
  Lines        9462     9460    -2     
  Branches     2199     2199           
=======================================
- Hits         9027     9026    -1     
+ Misses        435      434    -1     

Files with missing lines	Coverage Δ
packages/opentelemetry-resources/src/utils.ts	100.00% <ø> (+14.28%)	⬆️

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[pichlermarc]

nice, thanks!

[otelbot]

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