Add foreign key constraint for creator_id

This foreign key constrains will prevents creator record
deletion from users table.

src/stubs/database/migrations/migration-create.stub

@@ -19,6 +19,8 @@ class CreateMastersTable extends Migration
             $table->string('description')->nullable();
             $table->unsignedInteger('creator_id');
             $table->timestamps();
+
+            $table->foreign('creator_id')->references('id')->on('users')->onDelete('restrict');
         });
     }
 

tests/Generators/MigrationGeneratorTest.php

@@ -34,6 +34,8 @@ class Create{$this->plural_model_name}Table extends Migration
             \$table->string('description')->nullable();
             \$table->unsignedInteger('creator_id');
             \$table->timestamps();
+
+            \$table->foreign('creator_id')->references('id')->on('users')->onDelete('restrict');
         });
     }