[App Service] sample web app deployed automatically from GitHub

[metacpp]

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This issue is a: (mark with an x)

• bug report
• request for new sample
• documentation issue or request
• regression (a behavior that used to work and stopped in a new release)

Steps to reproduce:

Errors and log messages:

Expected behavior:

Provide sample about how to use source control as deployment option for web app.

OS and Go versions:

Further info: