docs: Add NIC multiple regex paths to vsr

[javorszky]

Proposed changes

NIC 5.5.0 will support adding multiple regex paths to a single VSR. This will cut down on maintenance costs for customers who have split deployment responsibilities.

This PR adds the necessary information to the VS/VSR configuration reference, and a separate page detailing how the new functionality works in detail, including path normalization.

nginx/kubernetes-ingress#8742

Checklist

Before sharing this pull request, I completed the following checklist:

• I read the Contributing guidelines
• My branch adheres to the Git conventions
• My content changes adhere to the F5 Technical Writing Style Guide
• If my changes involve potentially sensitive information¹, I have assessed the possible impact
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Footnotes

1. Potentially sensitive information includes personally identify information (PII), authentication credentials, and live URLs. Refer to the style guide for guidance about placeholder content. ↩

[github-actions]

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