Improve the look of the token access table

What does this MR do and why?

Improve the look of the token access table

Add group/project icon
Add group/project avatar
Make project path a link to the project

Changelog: changed

to do list

• rebase once Allow groups to be added to the inbound allowlist (!151693 - merged) is merged
• add tooltips to the group and project icons (!151693 (comment 1897903744), !151693 (comment 1897903766))
• targetPath is confusing, use groupOrProject consistently (!151693 (comment 1897903785))
  - [ ] show empty text when no groups/projects have been added, rename scope to allowlist (!151693 (comment 1897903814))
  • removed the empty text because the table is never empty (a project can always access itself)
• check small viewport width table layout, horizontal and vertical alignment of rows/columns (!151693 (comment 1897903843))
• consider using a single table for all groups/projects to allow for future sorting/filtering (!151693 (comment 1897903772))
• rebase once !151704 (merged) is merged (will conflict now that we changed the card-table header there)
• suggestion (non-blocking): WDYT about adding gl-mb-0 here to avoid the bottom spacing of the paragraph? - !151704 (comment 1912505746)
• suggestion (non-blocking): due to gl-new-card-title being applied on the div and not anymore on h5, the margin is not set to 0 and there is extra spacing causing the title to not be nicely aligned with the button anymore [...] WDYT about adding gl-my-0 and gl-items-center? !151704 (comment 1912505736)

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Screenshots or screen recordings

Before	After

How to set up and validate locally

1. navigate to a project
2. in the sidebar, choose Settings => CI/CD
3. expand the Token Access section
4. add groups and projects to the project's allowlist
5. for each group/project, there should be:
   • a group/project icon on the left
   • the group/project avatar
   • the path of the group/project, which is now shown as a link to it

Related to #415519 (closed)