Fix: Apply a default defalutValue on ArrayInput

[erwanMarmelab]

Problem

Instead of all other inputs, ArrayInput doesn't provide a default defalutValue.
This is an issue when calling the react-hook-form reset method as react-hook-form will not reset fields that don't have default values.

Solution

Apply a default defalutValue on ArrayInput

Additional Checks

• The PR targets master for a bugfix or a documentation fix, or next for a feature

[djhi]

A test that call reset on an ArrayField inside a Create would be great