fix: Enable union type support in @opentelemetry/instrumentation-graphql (#1506)

[nitrofski]

Which problem is this PR solving?

Fixes #1506.

Short description of the changes

Enable support for installing field instrumentation on union types.

The "type unwrap" logic was generalized to support unwrapping to a list of types. It is now a recursive function rather than a loop. The new unwrapping has been implemented in a way that is more agreeable to TypeScript.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: david-luna / name: David Luna (0c5ef73)
• ✅ login: nitrofski / name: Vincent Fortin (8a08afd, 9f087c7, b174583)
• ✅ login: nitrofski / name: nitrofski (c7f51ad, 2da8f10)

[david-luna]

Hi @nitrofski and thanks for your contribution.

I order to proceed we need a couple of things:

• a recent PR which changes the folder structure has ben merged. Please sync your PR with the latest changes
• you need to sing the CLA so we can run the CI

Cheers

[dyladan]

@obecny can you please take a look at this?

[nitrofski]

@david-luna

I merged with main.

There are issues with CLA approval at my company at the moment, which we are working on getting resolved. I will sign as soon as that's done. Sorry for the delay.

[nitrofski]

CLA issues have been resolved.

[dyladan]

@obecny can you please take a look at this?

[nitrofski]

Good day,

This hasn't seen feedback in over a month. Is there anything I can do to help get attention on this PR?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.45%. Comparing base (9d689e1) to head (0c5ef73).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2923   +/-   ##
=======================================
  Coverage   91.44%   91.45%           
=======================================
  Files         146      146           
  Lines        8194     8202    +8     
  Branches     1846     1848    +2     
=======================================
+ Hits         7493     7501    +8     
  Misses        701      701           

Flag	Coverage Δ
instrumentation-graphql	94.10% <100.00%> (+0.10%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
packages/instrumentation-graphql/src/utils.ts	93.45% <100.00%> (+0.25%)	⬆️

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