[issuegenerator] Ping pr author of failing test

[jelly-afk]

fixes #1182

autogenerated issues/comments now contain pr number of a failing test's pr
issuegenerator now pings author of a failing test's pr

[codecov]

Codecov Report

❌ Patch coverage is 32.21477% with 101 lines in your changes missing coverage. Please review.
✅ Project coverage is 61.33%. Comparing base (25ee987) to head (85bd2ae).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
issuegenerator/internal/github/client.go	32.43%	96 Missing and 4 partials ⚠️
issuegenerator/main.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1267      +/-   ##
==========================================
- Coverage   62.44%   61.33%   -1.11%     
==========================================
  Files          65       65              
  Lines        4026     4172     +146     
==========================================
+ Hits         2514     2559      +45     
- Misses       1280     1377      +97     
- Partials      232      236       +4     

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[mx-psi]

This does not seem to work in practice 🤔 Example workflow: https://github.com/open-telemetry/opentelemetry-collector-contrib/actions/runs/18347481850/job/52259572883

There are two issues, the first one is a permissions issue:

2025-10-08T14:27:26.435Z	WARN	github/client.go:388	Failed to comment on PR	{"pr_number": 43246, "error": "POST https://api.github.com/repos/open-telemetry/opentelemetry-collector-contrib/issues/43246/comments: 403 Resource not accessible by integration []"}
go.opentelemetry.io/build-tools/issuegenerator/internal/github.(*Client).CommentOnPR
	go.opentelemetry.io/build-tools/[email protected]/internal/github/client.go:388
go.opentelemetry.io/build-tools/issuegenerator/internal/github.(*Client).CommentOnIssue
	go.opentelemetry.io/build-tools/[email protected]/internal/github/client.go:237
main.main
	go.opentelemetry.io/build-tools/[email protected]/main.go:81
runtime.main

The second one is that the comments do not seem to have the PR number, see open-telemetry/opentelemetry-collector-contrib#43116 (comment)

I can try and look at the first one, but I don't understand why the second one happened. @jelly-afk do you want to take a look?