Sharing a copy of your code to GitHub using Pipelines

 How to add/update files in git repository from Azure DevOps Pipeline

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Azure DevOps YAML Pipeline sharing a copy of your code to GitHub

By default the source files are checked out to the Build.SourcesDirectory (e.g : Directory: D:\a\1\s), it can be considered as a temporary git repository.

Run below command line to push commits:

Please note that you need to Grant version control permissions to the build service and enable Allow scripts to access the system token.