Support for scrolling and column groups

[mr83-uw]

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CodeSandbox Case (Bug Reports)
Please demonstrate your case at CodeSandbox by using the issue template below. Issues without a test case have much less possibility to be reviewed in detail and assisted.

https://codesandbox.io/s/charming-jennings-zvm09

Current behavior
Combining scrolling behavior causes column groups to not render properly

Expected behavior
Be able to use column groups with scrolling

Minimal reproduction of the problem with instructions
https://codesandbox.io/s/charming-jennings-zvm09

Please tell us about your environment:
Windows 10, Eclipse IDE, vue-cli

• Vue version: 3.X
  3.0.11

• PrimeVue version: 3.4.X
  3.5.0

• Browser: [all | Chrome XX | Firefox XX | IE XX | Safari XX | Mobile Chrome XX | Android X.X Web Browser | iOS XX Safari | iOS XX UIWebView | iOS XX WKWebView ]
  Chrome 90