Bump am_list to v1

[gagbo]

If am_list is stable, then diff-metrics would be able to always fetch the latest version of am_list without worrying about breaking changes.

That means diff-metrics would always compute the best possible view of the repository with the annotated functions.

Having a stable release mostly means:

• no breaking change in the flags of the CLI
• no breaking change in the JSON returned in the result.