Merge pull request #73 from SignPath/feature/azure-permissions

adds info for permissions for Azure DevOps

Author: paulsavoie

docs/trusted-build-systems/azure-devops.md

@@ -150,3 +150,8 @@ Allows to restrict the Azure DevOps build pipelines with the following policies:
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+
+{:.panel.info}
+> **Required permissions**
+>
+> Azure DevOps automatically creates a "Build Service" user for each project. This user must be granted "Reader" permissions for Agent pools to determine whether self-hosted agents were used.