[Modules] Updated Virtual Network Gateway Module API Version (2022-07-01)

[ahmadabdalla]

closes #2669

Description

Updated virtual network gateway module to the latest API version. And added new properties and natRules child module, and updated test cases to leverage new properties

Pipeline references

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Type of Change

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Checklist

• I'm sure there are no other open Pull Requests for the same update/change
• My corresponding pipelines / checks run clean and green without any errors or warnings
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (readme)
• I did format my code