[Azure CNS] Bug Fix for Overlay Subnet Expansion

[rejain456]

Reason for Change:

Issue Fixed:

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• relevant PR labels added

Notes:

[Copilot]

Pull Request Overview

This PR fixes a bug in Azure CNS where overlay subnet expansions were incorrectly triggering PrimaryCA mismatch errors. The fix adds scenario-aware validation that skips the subnet comparison check for overlay network containers when subnet expansion occurs.

Key Changes:

• Added Scenario field to CreateNetworkContainerRequest to track the network container type
• Modified validation logic to skip PrimaryCA comparison for overlay scenarios
• Populated the Scenario field in both dynamic and static NC request creation paths

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
cns/NetworkContainerContract.go	Adds Scenario field to track NC type
cns/restserver/internalapi.go	Implements conditional PrimaryCA validation based on scenario
cns/kubecontroller/nodenetworkconfig/conversion.go	Sets Scenario field for dynamic NC requests
cns/kubecontroller/nodenetworkconfig/conversion_linux.go	Sets Scenario field for static NC requests
cns/restserver/util.go	Removes unnecessary blank line

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