Track down and switch over HAML loading spinners for Manage areas
In https://gitlab.com/gitlab-org/gitlab-ce/issues/20084#note_136312823, we discussed next steps for updating loading spinners in GitLab to use our new gitlab-ui
component.
We need to update old spinners in HAML files. We should list these for Manage related areas (projects, groups, navigation, etc) and update them to use the new component we're updating in https://gitlab.com/gitlab-org/gitlab-ce/issues/20084.