Add support in morphTo relationship for null values (1547) (#1549)

Co-authored-by: Barry vd. Heuvel <[email protected]>

tests/Console/ModelsCommand/migrations/____morphs_table.php

@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+class MorphsTable extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('morphs', function (Blueprint $table) {
+            $table->morphs('relation_morph_to');
+            $table->nullableMorphs('nullable_relation_morph_to');
+        });
+    }
+}