Highcharts Graphs are not adapting Windows High contrast Theme.

[msftedad]

User Impact
User who use High Contrast theme will be impacted here as they will not grab information given in the Graphs as graphs are not adapting high Contrast Theme.

Expected behaviour
Graphs should adapt high contrast Theme.

Actual behaviour
Graphs are not adapting high contrast Theme.

Test Environment:
OS: Windows 10 Version Dev (OS Build 21343.1000)
Browser: Microsoft Edge Dev Build 91.0.864.1
URL: https://www.highcharts.com/demo/pie-legend

Steps to reproduce

1. Open https://www.highcharts.com/demo/pie-legend on browser.
2. Open Windows Settings app using 'Windows + i' Key.
3. Navigate to 'Ease of Access' menu item and activate it.
4. Then Navigate to 'High Contrast' tab and activate it.
5. Then switch ON 'Turn on high Contrast' toggle button.
6. Select White/Black theme from 'Choose a theme' combo box.
7. Verify that Graphs are adapting high contrast themes or not.

Attachments.Files.zip

[pawellysy]

Closing as a duplicate of #15567