Hub details further style adjustments

[lusloher]

Further design syncing on the Hub Details work:

• [x] remove code block background colours
• [x] remove the solid background in implementation
• [x] introduce variety in the tag colors
• [x] make sure all text fonts match up (colors, size, weight, spacing etc)
• [x] change colour of links
• [x] remove the current 'Hub' header and replace it with the new header from the designs

Anything else that has visual discrepancies. Try putting the designs side by side and checking every little bit piece by piece.

┆Issue is synchronized with this Asana task by Unito

[lusloher]

Link to subfeature: https://jinaai.productboard.com/feature-board/planning/features/8035166