clarkeash has created Issue #2725: First argument of MongoDB\Laravel\Query\Builder::where must be a field path as "string". Got "null" in laravel-mongodb. This Jira ticket was filed by GromNaN

Issue Text:

• Laravel-mongodb Version: 4.1.1
• PHP Version: 8.3.2
• Database Driver & Version: 1.17.2

Description: I am currently upgrading to Laravel 10 and v4 of this library and when calling save on an embeded document I get the error: `First argument of MongoDB\Laravel\Query\Builder::where must be a field path as "string". Got "null"`

Steps to reproduce

I have the following models (simplified for clarity)
```php
class Account extends Model {
public function stripe(): EmbedsOne

{ return $this->embedsOne(Stripe::class); }

}
```

```php
class Stripe extends Model {}
```

Then when I try to update the stripe subdocument like so:
```php
$account = Account::find(...);
$stripe = $account->stripe;
$stripe->subscription = ['some data'];
$stripe->save();
```

Expected behaviour

Tell us what should happen `jenssegers/mongodb` 3.9 it would save the data just fine.

Actual behaviour

```
1) Tests\Feature\Actions\Stripe\CancelPendingChangeTest::it_will_cancel_a_pending_modification
InvalidArgumentException: First argument of MongoDB\Laravel\Query\Builder::where must be a field path as "string". Got "null"

/Users/clarkeash/code/sites/billing/vendor/mongodb/laravel-mongodb/src/Query/Builder.php:1012
/Users/clarkeash/code/sites/billing/vendor/laravel/framework/src/Illuminate/Database/Eloquent/Builder.php:302
/Users/clarkeash/code/sites/billing/vendor/laravel/framework/src/Illuminate/Database/Eloquent/Model.php:1254
/Users/clarkeash/code/sites/billing/vendor/laravel/framework/src/Illuminate/Database/Eloquent/Model.php:1213
/Users/clarkeash/code/sites/billing/vendor/laravel/framework/src/Illuminate/Database/Eloquent/Model.php:1130
/Users/clarkeash/code/sites/billing/vendor/mongodb/laravel-mongodb/src/Eloquent/Model.php:737
/Users/clarkeash/code/sites/billing/app/Actions/Stripe/StoreSubscriptionInformation.php:82
/Users/clarkeash/code/sites/billing/vendor/lorisleiva/laravel-actions/src/Concerns/AsObject.php:24
/Users/clarkeash/code/sites/billing/tests/Feature/Actions/Stripe/CancelPendingChangeTest.php:41
```

I am unsure if this is a bug or if I have missed something, can you point me in the right direction? Thanks