fix: avoid error when building package importing skeleton with remote components

[AustinAbro321]

Description

During the create refactor the logic was changed to error when pulling a component from a skeleton package without an associated layer in the oci manifests. This leads to errors when a component is imported that only has remote resources. A tarball isn't created for that component in the skeleton package, and therefore a layer is not created for that component. This changes the logic to follow how it was originally in importchain.fetchOCISkeleton

Related Issue

Fixes #3469

Checklist before merging

• Test, docs, adr added or updated as needed
• Contributor Guide Steps followed

[netlify]

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[codecov]

Codecov Report

Attention: Patch coverage is 3.03030% with 32 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/internal/packager2/layout/import.go	3.03%	32 Missing ⚠️

Files with missing lines	Coverage Δ
src/internal/packager2/layout/import.go	38.01% <3.03%> (-1.15%)	⬇️

[mkcp]

LGTM