Azure DevOps Git Credential Issues
I am not sure if this is a common problem. It was difficult to find forum posts or articles on the exact issue.
Deploying Azure resources to multiple resource groups
Azure Resource Manager (ARM) templates provide an excellent, built-in resource configuration and deployment solution. You can find a wealth of templates for deploying anything from a Wordpress site on Azure App Service, to a full HDInsight cluster on a private VNET.
Authentication using Azure Management SDK
If you want to programmatically update Azure Resource configurations you have a number of options.