feat: new module for app configuration

[sunilthorat09]

Description

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Closes #334

[sunilthorat09]

@dciborow @shenglol Can you please register 'Microsoft.AppConfiguration' resource provider on the Test subscription(edf507a2-6235-46c5-b560-fd463ba2e771). Test failure logs.

[shenglol]

Microsoft.AppConfiguration

Done.

[shenglol]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[sunilthorat09]

@dciborow @shenglol Can you please help to onboard this new module manifest to MCR and also help to review the code. Thanks!.

[shenglol]

Will merge this once the MCR manifest PR is merged.