feat: #6929 add ResourcePrefix to imagebuilder

[Mideky-hub]

Description of changes

• Added support for resource_prefiex in the ImageBuilder module.
• This ensures that the resource_prefiex value specified in the configuration is respected during image creation, aligning behavior with what’s currently expected in cluster builds.
• This change was necessary because previously, the resource_prefiex was ignored in the ImageBuilder, leading to inconsistencies and user confusion as reported in issue [#6929](Feature Request: Support "ResourcePrefix:" argument for image-builder pipeline #6929).

Tests

• Automated Tests:

  • Extended existing unit tests to include cases where resource_prefiex is provided.
  • Verified correct behavior when resource_prefiex is set and when omitted (default behavior).

• Manual Tests:

  • Built custom images with pcluster build-image using a configuration that includes resource_prefiex, validated that it is correctly applied throughout the image build lifecycle.

References

• Impacted issue: [#6929](Feature Request: Support "ResourcePrefix:" argument for image-builder pipeline #6929)
• Related areas: cluster configuration handling, ImageBuilder component
• Documentation reference: [ParallelCluster Configuration Schema](https://docs.aws.amazon.com/parallelcluster/latest/ug/configuration.html#build-image-section)

Checklist

• Pointing to the correct branch.
• Clear commit messages explaining what and why.
• Unit/integration tests updated to cover the new logic.
• Verified if documentation needs updates (will open follow-up PR if necessary).
• Confirmed change aligns with [contributing guidelines](../CONTRIBUTING.md).

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.