orm 多库链接的情况无法在模型中通过$connection指定连接

[huey-deng]

orm 多库链接的情况无法在模型中通过$connection指定连接
指定第二个库时，查询列表会报错 说第一个库不存在某表
排查到原因是
` protected function selectInput(Request $request): array
{
$field = $request->get('field');
$order = $request->get('order', 'asc');
$format = $request->get('format', 'normal');
$limit = (int)$request->get('limit', $format === 'tree' ? 1000 : 10);
$limit = $limit <= 0 ? 10 : $limit;
$order = $order === 'asc' ? 'asc' : 'desc';
$where = $request->get();
$page = (int)$request->get('page');
$page = $page > 0 ? $page : 1;
$table = config('plugin.admin.database.connections.mysql.prefix') . $this->model->getTable();

    $allow_column = Util::db()->select("desc `$table`");
    if (!$allow_column) {
        throw new BusinessException('表不存在');
    }
    $allow_column = array_column($allow_column, 'Field', 'Field');
    if (!in_array($field, $allow_column)) {
        $field = null;
    }
    foreach ($where as $column => $value) {
        if (
            $value === '' || !isset($allow_column[$column]) ||
            is_array($value) && (empty($value) || !in_array($value[0], ['null', 'not null']) && !isset($value[1]))
        ) {
            unset($where[$column]);
        }
    }
    // 按照数据限制字段返回数据
    if (!Auth::isSuperAdmin()) {
        if ($this->dataLimit === 'personal') {
            $where[$this->dataLimitField] = admin_id();
        } elseif ($this->dataLimit === 'auth') {
            $primary_key = $this->model->getKeyName();
            if (!Auth::isSuperAdmin() && (!isset($where[$primary_key]) || $this->dataLimitField != $primary_key)) {
                $where[$this->dataLimitField] = ['in', Auth::getScopeAdminIds(true)];
            }
        }
    }
    return [$where, $format, $limit, $field, $order, $page];
}`

中config('plugin.admin.database.connections.mysql.prefix') 写死了这个mysql