Angular: Renaming the '.angular-cli.json' file to 'angular.json' breaks the official template

🐛 bug report

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Description of the problem

Renaming the '.angular-cli.json' (which is deprecated since Angular v6 - 2018.05) file to now standard 'angular.json' breaks the angular official template

How has this issue affected you? What are you trying to accomplish?

The fact that the Angular configuration file (angular.json) is not complying to the frameworks standard format leads to broken workspaces as soon as you have a more complex application. This limitation practically makes Codesandbox unusable for real life examples.

To Reproduce

1. Create a standard Angular sandbox
2. Rename '.angular-cli.json' to 'angular.json'

Link to sandbox: sandbox-with-renamed-config-file (optional)

Your Environment

Start by reproducing the problem in the linked sandbox, keen-williamson-t6do5, using the listed steps to rename .angular-cli.json to angular.json. Trace how the official Angular template discovers and loads its configuration, then verify that a renamed angular.json supports the template without breaking more complex workspaces.