Add text color to callout

[janniks]

The text color of callouts is missing. Background color works, but there are no non-background _co css rules in styles.css, so text coloring of callouts does not work yet.

---

I fixed this by adding the same class without the _co before the existing class. This way the text color (first class) will not be overwritten (e.g. because no .notion-teal_co rule exists) and the background color will still use the custom _co rules (e.g. because .notion-teal_backgorund is overwritten by.notion-teal_backgorund_co)

You can see the working callout text color in the first block of this Notion page: 8c1ab01960b049f6a282dda64a94afc7

[tobiaslins]

Thank you @janniks :)