a11y: Table block inverted style link color contrast too low

[jackahl]

Describe the bug
When using the table block with inverted colors, the contrast between the bg and links is too low. We should choose a better blue here

To Reproduce
Steps to reproduce the behavior:

1. Go to https://volto.demo.plone.org/
2. Add a new table block
3. invert its color and add a inline link in on of the table cells
4. Use either axe or Colour contrast Analyser Software to check for sufficient contrast

--> contrast is not sufficient

Expected behavior
Contrast should be sufficient

Screenshot

Software:

• OS: OSX (does not really matter)
• Browser: any
• Volto Version: latest main branch checkout
• Plone Version: 6

[pnicolli]

Fixed by #6333