At least one of arrays nodes must be filled

#### Support plan

* *is this issue currently blocking your project?* (yes/no): NO
* *is this issue affecting a production system?* (yes/no): NO

#### Context

* *node version*: v14.17.0
* *module version*: 17.4.2
* *environment* (e.g. node, browser, native): node and browser
* *used with* (e.g. hapi application, another framework, standalone, ...): standalone
* *any other relevant information*:

#### How can we help?

At least one of arrays nodes must be filled, If all arrays nodes are empty, abort validation.

```js
const validator = Joi.array().items(Joi.object({
day: Joi.string().required(),
nodes: Joi.array().items(Joi.array().items(Joi.number()).length(2))
})).length(7)

//not valid
const week = [
{day: 'monday', nodes: []},
{day: 'tuesday', nodes: []},
{day: 'wednessday', nodes: []},
]

//valid
const week = [
{day: 'monday', nodes: [[5,7]]},
{day: 'tuesday', nodes: []},
{day: 'wednessday', nodes: []},
]
```

Reproduce the reported Joi.array().items() schema with the invalid and valid week examples from the issue. Start by tracing how Joi validates the nested nodes arrays and review nearby validation tests; done means all-empty nodes are rejected while a week with at least one populated nodes array is accepted.

Written by the indexing model from the issue text.