UI polish for Geo pages

Use geo-nodes sprite icon where appropriate:
Instead of using the fontawesome globe icon, use the geo-nodes icon
for Geo related action.

Closes gitlab-org/gitlab-ee#4425.

app/helpers/button_helper.rb

@@ -112,7 +112,7 @@ module ButtonHelper
   def geo_button(modal_target: nil)
     data = { placement: 'bottom', container: 'body', toggle: 'modal', target: modal_target }
     content_tag :button,
-                icon('globe'),
+                sprite_icon('geo-nodes', size: 15),
                 class: 'btn btn-geo has-tooltip',
                 data: data,
                 type: :button,

app/views/layouts/nav/_dashboard.html.haml

@@ -63,4 +63,4 @@
   - if Gitlab::Geo.secondary? && Gitlab::Geo.primary_node_configured?
     %li
       = link_to Gitlab::Geo.primary_node.url, title: 'Go to primary node', data: {toggle: 'tooltip', placement: 'bottom', container: 'body'} do
-        = icon('globe fw')
+        = sprite_icon('geo-nodes', size: 18)

changelogs/unreleased-ee/tc-geo-ux-polish.yml

+---
+title: Geo UI polish
+merge_request:
+author:
+type: changed