[10.x] Add "dot" method to Illuminate\Support\Collection class

[medeirosinacio]

This PR adds the dot method to the Illuminate\Support\Collection class in Laravel.

Additionally, I recently had a need to perform the dot operation on an array, extract 5 items from the flattened result, and then convert it back to a multi-dimensional array using the undot method. Unfortunately, achieving this with the current implementation required me to write the following code:

Arr::undot(array_slice(Arr::dot($keys), 0, 5))

With this PR, users can now easily achieve the same result using the following code:

collect($keys)->dot()->take(5)->undot()

This simplifies the code and makes it more readable, providing a better developer experience for users of Laravel's Illuminate\Support\Collection class.

[BafS]

Me thinking dot would do a dot product, the name is confusing.