I am trying to use the Azure DevOps pipeline caching mechanism like described here https://learn.microsoft.com/en-us/azure/devops/pipelines/release/caching?view=azure-devops but I am struggling with the term "main branch" that is listed in the tables located here https://learn.microsoft.com/en-us/azure/devops/pipelines/release/caching?view=azure-devops#cache-isolation-and-security.
What means "main" here? Is it literally the branch called "main" or can this be configured somehow?