fix: dashboard sharing UI don't use red for remove collaborator

[pauldambra]

Problem

closes #9239

Changes

• removes some styles by using utility classes
• removes grey background from collaborator rows
• uses tertiary primary-alt for remove collaborator buttons
• don't show a remove collaborator button if you can't remove the collaborator

How did you test this code?

running it locally and seeing it happen

[benjackwhite]

lgtm

[Twixes]

This is looking pretty good, though a couple of things about the design irk me:

1. There are two styles of subheadings in this modal – "Collaborators" should use the same style as "Project members with access":
   
2. I can see the motivation to center things behind this padding, but when I opened the modal "can edit" looked kind of misaligned to me:
   

[pauldambra]

Updated @Twixes

[Twixes]

It irks less now, thanks! 😄 I'll let @clarkus have the final word just in case.

[pauldambra]

cherry-picked into 1.39.0