[12.x] Adds support for multiple models on single assertion call (#10642)

* [12.x] Adds support for multiple models on single assertion call

* Update database-testing.md

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Co-authored-by: Taylor Otwell <[email protected]>

Author: DarkGhostHunter

database-testing.md

@@ -254,7 +254,7 @@ $this->assertNotSoftDeleted($user);
 <a name="assert-model-exists"></a>
 #### assertModelExists
 
-Assert that a given model exists in the database:
+Assert that a given model or collection of models exist in the database:
 
 ```php
 use App\Models\User;
@@ -267,7 +267,7 @@ $this->assertModelExists($user);
 <a name="assert-model-missing"></a>
 #### assertModelMissing
 
-Assert that a given model does not exist in the database:
+Assert that a given model or collection of models do not exist in the database:
 
 ```php
 use App\Models\User;