[7.x] Align (fix) nested arrays support for assertViewHas & assertViewMissing

[claudiodekker]

This PR completes/fixes the inconsistent behaviour regarding nested array support introduced in #30837

It also re-aligns the assertViewMissing method in a similar fashion, to be compatible with the assertViewHas changes proposed in this PR.

---

assertViewHas

These were already possible:

$response->assertViewHas('foo');
$response->assertViewHas('foo', 'bar');
$response->assertViewHas('foo.nested', 'bar');

However, this one wasn't:

$response->assertViewHas('foo.nested');

assertViewMissing

Similarly, this was already possible:

$response->assertViewMissing('foo');

But this one wasn't:

$response->assertViewMissing('foo.nested');

[driesvints]

@claudiodekker just for future references: any bug fix can be sent to 6.x instead which will get merged with upstream branches.

[claudiodekker]

@driesvints Ah, I'll keep it in mind next time. I was looking at https://laravel.com/docs/7.x/contributions#which-branch, which told me to target the latest LTS?

Update: Oops, I only now noticed the (LTS) flag appended to 6 😅

[driesvints]

6.x is the current LTS version yes. I've backported this.