fix(terraform): ensure consistent path handling across OS

[nikpivkin]

Description

Trivy creates a virtual filesystem for post-analysers, so path handling should not depend on the OS.

Checklist

• I've read the guidelines for contributing to this repository.
• I've followed the conventions in the PR title.
• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
• I've added usage information (if the PR introduces new options)
• I've included a "before" and "after" example to the description (if the PR is a user interface change).

[simar7]

thanks, lgtm

[knqyf263]

@simar7 You can merge PRs if the change is only in pkg/iac or other IaC dirs, like you guys did in defsec/trivy-iac. If PR includes changes in other areas, it would be appreciated if you would wait for my review.

[simar7]

@simar7 You can merge PRs if the change is only in pkg/iac or other IaC dirs, like you guys did in defsec/trivy-iac. If PR includes changes in other areas, it would be appreciated if you would wait for my review.

sounds good!