Improvements for infra deployment using azure devops

[ZahraAsadiMSFT]

Motivation and Context

Description

This PR includes several improvements and modifications to the infrastructure deployment setup, aiming to enhance consistency and ease of use.

Changes Made

1. Incorporated storage-account.bicep into main.bicep:

• Consolidated the storage account deployment logic into the main Bicep file for better maintainability and clarity.

2. Modified main.parameters.json to reflect resources addressed in main.bicep:

• Updated parameters to include appServicePlanName, cosmosAccountName, backendServiceName, resourceGroupName, and storageAccountName.

3. Standardized principalType across templates:

• Changed principalType from 'User' to 'ServicePrincipal' in both main.bicep and docprep.bicep.
• Ensured consistency and avoided potential issues with mixed principal types.

4. Added Azure Pipelines configuration:

• Created .azure-pipelines folder.
• Added azure-pipeline.yml as a template for deploying the infrastructure using Azure DevOps.
• This pipeline includes steps for installing Bicep, replacing placeholders in parameter files, and deploying the Bicep templates

Contribution Checklist

• I have built and tested the code locally and in a deployed app
• For frontend changes, I have pulled the latest code from main, built the frontend, and committed all static files.
• This is a change for all users of this app. No code or asset is specific to my use case or my organization.
• I didn't break any existing functionality 😄