Migrate a couple fetch calls to services, fix some <a href="#"> links.

...admin/settings/components/widgets/CustomGeoJSONWidget.jsx

frontend/src/metabase/components/Logs.jsx

frontend/src/metabase/dashboard/components/DashCard.jsx

frontend/src/metabase/home/components/Activity.jsx

frontend/src/metabase/home/components/NextStep.jsx

frontend/src/metabase/lib/api.js

frontend/src/metabase/routes-internal.js

frontend/src/metabase/routes.jsx

frontend/src/metabase/services.js

frontend/src/metabase/setup/components/DatabaseStep.jsx