[Modules]: Azure Database for PostgreSQL Flexible Servers Module

[ahmadabdalla]

Description

Closes #1751

• Enabled the PostgreSQL - Flexible Server Module

• Added a new dependency vnet and a private dns zone for the module.

• Contains 3 child modules (configurations, firewallrules, databases)

• Contains 3 scenarios for parameter file testing to cover all parameter combinations

NOTE: The nature of the of this resource type 'may' sometimes fail when adding the 'configurations', especially when having more than one in the array. This is not a CARML issue. The error returned is 'InternalServerError'. However, after performing multiple tests. The likelihood of this happening is small. I suggested initially whether we should remove this parameter from being tested, but I prefer to have it. Our pipelines retry 3 times for a deployment and that seems to be sufficient

Pipeline references

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Pipeline

Type of Change

• 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