Expected location for `assertCreatedWithClientId`

[lindyhopchris]

At the moment the expected location when calling assertCreatedWithClientId must not contain the expected id. This is because the assertion reads the id from the expected resource array and appends it to the provided URI.

However, this doesn't read nicely in tests. For example:

$post = Post::factory()->make();

$data = [
    'type' => 'posts',
    'id' => '7088eccc-a7cd-46f6-81f9-c553c9065dbd',
    'attributes' => [
        'content' => $post->content,
        'slug' => $post->slug,
        'title' => $post->title,
    ],
];

$response = $this
    ->jsonApi()
    ->expects('posts')
    ->withData($data)
    ->post('/api/v1/posts', $data);

$response->assertCreatedWithClientId(
    'http://localhost/api/v1/posts',
    $data
);

I think it reads better to do this:

$response->assertCreatedWithClientId(
    'http://localhost/api/v1/posts/7088eccc-a7cd-46f6-81f9-c553c9065dbd',
    $data
);

To fix in a non-breaking way, it would be good if the assertion accepted either. i.e. it can read the id from the provided $data, and check whether the URI already contains that id. If not, it can append it.