Fix Undefined index:primary for SQLITE

[neatstudio]

error : local.ERROR: Undefined index: primary {"exception":"[object] (ErrorException(code: 0): Undefined index: primary at /Volumes/documents/server/wwwroot/wechaty/crm.app.wechaty.net/vendor/reliese/laravel/src/Meta/Sqlite/Schema.php:147)

update this function:
before:

    /**
     * @param \Reliese\Meta\Blueprint $blueprint
     * @todo: Support named primary keys
     */
    protected function fillPrimaryKey(Blueprint $blueprint)
    {
        $indexes = $this->manager()->listTableIndexes($blueprint->table());

        $key = [
            'name' => 'primary',
            'index' => '',
            'columns' =>$indexes['primary']->getColumns(),
        ];

        $blueprint->withPrimaryKey(new Fluent($key));
    }

after:

    /**
     * @param \Reliese\Meta\Blueprint $blueprint
     * @todo: Support named primary keys
     */
    protected function fillPrimaryKey(Blueprint $blueprint)
    {
        $indexes = $this->manager()->listTableIndexes($blueprint->table());

        $key = [
            'name' => 'primary',
            'index' => '',
            'columns' => optional($indexes['primary']??null)->getColumns(),
        ];

        $blueprint->withPrimaryKey(new Fluent($key));
    }