⬆️ Update `highcharts` to v11.4.8

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
highcharts (source)	11.4.7 -> 11.4.8

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Release Notes

highcharts/highcharts-dist (highcharts)

### [`v11.4.8`](https://togithub.com/highcharts/highcharts-dist/compare/v11.4.7...99133f67af9270308f0b60d67cb0fb1bc282d0f8) [Compare Source](https://togithub.com/highcharts/highcharts-dist/compare/v11.4.7...v11.4.8)

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Configuration

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