Remove typography styles for the navigation block

[unscripted]

What problem does this feature request address?

Currently, the theme's CSS sets several typography styles. This prevents changes in the editor from appearing on the front end. A specific use case where I encountered this issue is the styles for the header and footer needed to differ.

What is your proposed solution?

By completing the steps below, we would allow typography style changes made in the editor to affect the output of the navigation blocks.

1. Remove font weight, size and colors from the CSS.
2. Add the default desired font weight, size and color to the theme.json.
3. Remove "textTransform": "uppercase" from the core/navigation block in the theme.json.
4. Remove "fontWeight": false from the typography element of the theme.json

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