For security reasons you may want to store the pipelines to another repository than the one that the code is hosted. Lets say for example that you have your application code located on test-project/repository location but your pipelines are stored on the consoleapp1 repository. Also you want to have continuous integration and deployment for the repository on which the code is hosted, so when code is pushed to repository then the pipeline should trigger which is hosted on ConsoleApp1.
You can do that using the repositories resource of azure devops. You will need to define the repository and also configure trigger for this repository based on your strategy.
The final result would be the pipeline to run when code is commited on the code repository instead of the one that pipelines are hosted.