Remove `array` type

[donno2048]

There is no array type.

> typeof([])
'object'
> typeof(new Array())
'object'

And even in the same file at the tojson function it's not used:

https://github.com/mongodb/mongo/blob/2b0bab0e2355bba3276cb80e05d03812300d86b2/src/mongo/shell/types.js#L627-L662