Use mocha instead of ava for tests

[theethernaut]

TBD

[dapplion]

Do all of us agree on this one?

If so it should be done at once since it affects the entire codebase and can be disruptive to parallel work (for example typescript conversion https://github.com/aragon/aragon-cli/pull/1116)

[JovianBrowne]

All the tests we merged to jest and some of them are not passing which is probably due to issues on the CLI or apm.js

[JovianBrowne]

Will leave this issue open until all tests are passing and related issues are closed.

[nivida]

Thanks for the details. I will move the issue on Linear to the Blocked state.

[nivida]

In addition..: Can you add the reference to the related issues on Linear. Otherwise, it will be hard to keep track of.