fix: accept newline-separated manifest path lists

[evannaderi]

Description

MANIFESTPATH (Azure Pipelines) and DEPLOYMENTMANIFESTPATH (GitHub Actions) are passed to the manifests input of KubernetesManifest@1 and Azure/k8s-deploy, which accept multiple paths separated by newlines. The dirPath kind rejects newlines, so these templates can't be generated for more than one manifest path. This adds a dirPathList kind that validates each line with dirPathValidator and uses it for both variables. Both templates already render these values with jsonString, so the newlines stay inside a single YAML value.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Refactor

How Has This Been Tested?

• Unit Test: go test ./.... Adds validator cases, a render test for both templates with multiple paths, and a test that every dirPathList variable is rendered with jsonString.
• E2E Test:
• Other Test:

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[evannaderi]

@microsoft-github-policy-service agree company="Microsoft"

[Suneha Bose (bosesuneha)]

lgtm