[11.x] Add support for syncing associations with array or base collection of models

[diaafares]

During a code review for a teammate’s automated tests, I proposed the following change:

$tag = Tag::create([‘name’ => Str::random()]);
$tag2 = Tag::create([‘name’ => Str::random()]);

- $post->tags()->sync([$tag->id, $tag2->id]);
+ $post->tags()->sync([$tag, $tag2]);

However, he encountered an error when attempting to implement this change, despite I was very sure that I used sync with models before.

It appears that the current implementation of parseIds doesn't support passing models unless they are passed inside an Eloquent collection, so, to make it consistent, I updated the implementation to work with an array or base collection of models.

This will also be beneficial for situations when you already have an array of models:

- $post->tags()->sync(Arr::pluck($tags, 'id'));
+ $post->tags()->sync($tags);

Furthermore, it seems that there are currently no tests that cover the scenario of passing an Eloquent collection to the sync method, so I added a check for it inside my newly added test.