业务需求，默认是圆点，需要把线的由圆点改为线

红色线是理论，点是历史理论，绿色线是实际， 点是历史实际，在series里的顺序也是这样排的。

打印出来的params里的marker就是圆点，改这段代码就可以了

 tooltip: {
    trigger: 'axis',
    axisPointer: {
      crossStyle: {
        color: '#999'
      }
    },
    backgroundColor: appStore.getThemeObj['--xxx-content-bg'],
    borderColor: appStore.getThemeObj['--xxx-content-bg'],
    textStyle: {
      color: appStore.getThemeObj['--xxx-second-content-color']
    },
    confine: true,
    formatter(params) {
      let tip = ''
      let text
      let title
      const therolineMarker = `<span style="display:inline-block;margin-right:4px;width:10px;height:3px;line-height:3px;vertical-align:middle;background-color:#F63F3F;"></span>`
      const AclineMarker = `<span style="display:inline-block;margin-right:4px;width:10px;height:3px;line-height:3px;vertical-align:middle;background-color:#15D11E;"></span>`

      for(let i = 0; i < params.length; i++) {
        title = params[0].axisValueLabel + '<br />'
        if (params[i].componentSubType === 'line') {
          const name = params[i].seriesIndex === 0 ? '理论xxx：' : '实际xxx：'
          const lineStyle = params[i].seriesIndex === 0 ? therolineMarker : AclineMarker
          text = `${lineStyle}${name}${params[i].value[1]} ℃ <br />`
        }
        if (params[i].componentSubType === 'scatter') {
          const name = params[i].seriesIndex === 1 ? '历史理论xxx：' : '历史实际xxx：'
          text = `${params[i].marker}${name}${params[i].value[1]} ℃ <br />`
        }
        tip += text
      }
      // console.log(tip,'--tip--');
      return `${title}${tip}`
    },
  },