Add Schema import to ApprovalStateScopeTest

In this commit, Schema import has been added to the ApprovalStateScopeTest. This extra import is necessary for the functioning of our DB tests and ensures that the test for Approval Model states runs smoothly.

tests/Feature/Scopes/ApprovalStateScopeTest.php

@@ -7,6 +7,7 @@
 use Cjmellor\Approval\Models\Approval;
 use Cjmellor\Approval\Tests\Models\FakeModel;
 use Illuminate\Support\Facades\Event;
+use Illuminate\Support\Facades\Schema;
 
 test('Check if an Approval Model is approved', closure: function (): void {
     $this->approvalData = [