Labels are blinking on scroll

Hi guys,

I have some strange behaviour that I did not met before
My labels are blinking on scroll, see attached video in zip

Even set up `chartView.autoScaleMinMaxEnabled = false` not helped to fix it

Here my chart common setup:
```

chartView.noDataTextColor = #colorLiteral(red: 1, green: 1, blue: 1, alpha: 1)
chartView.noDataText = "The DATA WAS NOT FOUND"
chartView.chartDescription?.text = ""
chartView.scaleYEnabled = false
chartView.drawGridBackgroundEnabled = false
chartView.legend.enabled = false
chartView.highlightPerTapEnabled = false
chartView.pinchZoomEnabled = false
chartView.setScaleEnabled(false)
chartView.autoScaleMinMaxEnabled = false

chartView.xAxis.enabled = true
chartView.xAxis.axisMinimum = 0
chartView.xAxis.drawLabelsEnabled = true
chartView.xAxis.drawGridLinesEnabled = false
chartView.xAxis.granularityEnabled = true
chartView.xAxis.granularity = 1
chartView.xAxis.drawAxisLineEnabled = true
chartView.xAxis.labelPosition = .bottom

chartView.setVisibleXRangeMaximum(15)
```

I did not find any opened issue for such behaviour, so any help will be appreciated

[label blinking problem.mp4.zip](https://github.com/danielgindi/Charts/files/2514162/label.blinking.problem.mp4.zip)

Start by reproducing the label blinking with the chart setup in the issue and the attached video, then trace the label rendering behavior while scrolling. Done means the labels remain stable during scrolling with the reported configuration; no source file or test is identified in the issue.

Written by the indexing model from the issue text.