What problem does this feature solve?

In some cases, containLable is only expected to work on one of xAxis or YAxis.

grid.containLabel could be more flexiable to be configurated for xAxis and yAxis separately.

What does the proposed API look like?

grid.containLabel : boolean | { top: boolean; right: boolean; bottom: boolean; left: boolean }

grid: {
  containLabel: {
      top: true,
      right: true,
      // bottom: false as default
      // left: false as default
  }
}