Add versionFilePath to UseNode@1

[bdukes]

Context

Fixes #22131

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Task Name

UseNode@1

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Description

Adds a versionFilePath input to UseNode@1 so that version specs can be stored in a file (e.g. .nvmrc or .node-version), instead of duplicated in the Pipelines config.

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Risk Assessment (Low / Medium / High)

Low. This change is backwards compatible and requires a developer to opt in to using the new input.

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Change Behind Feature Flag (Yes / No)

This adds a new input field, I don't know whether or not that can be feature flagged.

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Tech Design / Approach

This approach used the same basic idea as NodeTool@0 and UseDotnet@2

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Documentation Changes Required (Yes/No)

Yes, there is a new input field.

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Unit Tests Added or Updated (Yes / No)

No

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Additional Testing Performed

Verified automated tests did not have additional failures.

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Logging Added/Updated (Yes/No)

No

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Telemetry Added/Updated (Yes/No)

No

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Rollback Scenario and Process (Yes/No)

No

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Dependency Impact Assessed and Regression Tested (Yes/No)

No

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Checklist

• Related issue linked (if applicable)
• Task version was bumped — see versioning guide
• Verified the task behaves as expected