Redesign Job token permissions section

We have a new design for the Settings -> CI/CD -> Job token permissions section. We need to implement the new design:

Before	After

Specifically:

1. For the group selector, change Add group or project to Group or project, and add the Choose a group or project to authorize access into this project sub-label. Change the width of the dropdown to match the design rather than stretching the entire width of the parent container.

2. For the added groups/projects table, remove the additional bottom padding so that each item is centered in its row. Add the Permissions column and hard-code each row to Default (user membership and role). We will add the fine-grained permissions in another issue.