fix(tooltip): legendFilter and shared tooltip

[pearmini]

Shared Tooltip

分组条形图，点击图例筛选，会导致tooltip名称丢失：

复现代码

export function mockIntervalShared(): G2Spec {
  return {
    type: 'interval',
    data: {
      value: [
        { color: '房地产', x: '20230702', y: 36049 },
        { color: '房地产', x: '20230703', y: 26229 },
        { color: '汽车', x: '20230702', y: 23016 },
        { color: '汽车', x: '20230703', y: 48280 },
      ],
    },
    encode: { x: 'x', y: 'y', color: 'color', series: 'color' },
    legend: { color: { title: false } },
    interaction: { tooltip: { shared: true } },
  };
}

修复方法

有 shared 配置的时候都算 group items.

[coveralls]

Pull Request Test Coverage Report for Build 6156659021

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.003%) to 88.481%

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Totals
Change from base Build 6155429720:	0.003%
Covered Lines:	9964
Relevant Lines:	10898

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💛 - Coveralls