[docs] Missing CSS classes section in API reference docs of CardHeader

[rithik56]

Related page

https://mui.com/material-ui/api/card-header/

Kind of issue

Missing information

Issue description

The CSS classes section inside API reference docs for CardHeader component is missing.

Context

The CSS classes section inside CardHeader docs should be present just like it is present for other components.

Search keywords: CardHeader

[sai6855]

Looking into it