Added poetry and yarn package support to recognize 403 Forbidden output

[Phavya-jfrog]

• All tests passed. If this feature is not already covered by the tests, I added new tests.
• All static analysis checks passed.
• This pull request is on the dev branch.
• I used gofmt for formatting the code before submitting the pull request.
• Appropriate label is added to the PR for auto generate release notes.

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Summary

Extends IsForbiddenOutput (utils/error.go) to recognize 403 Forbidden output from two more package managers, so we can see clearer auth errors instead of silently passing them through.

Packages added:

• Poetry, Yarn.

[github-actions]

All contributors have signed the CLA ✍️ ✅
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[Phavya-jfrog]

I have read the CLA Document and I hereby sign the CLA

[naveenku-jfrog]

PR description is not present, so can't review it.