Update link to documentation

Make link clear in note box

Also update strings to be translatable

app/views/clusters/clusters/index.html.haml

@@ -11,6 +11,13 @@
       .nav-text
         = s_("ClusterIntegration|Kubernetes clusters can be used to deploy applications and to provide Review Apps for this project")
       = render 'clusters/clusters/buttons'
+
+    - if @clusters.length > clusterable.clusters.length
+      .bs-callout.bs-callout-info
+        = s_("ClusterIntegration|Clusters are utilized by selecting the nearest ancestor with a matching environment scope. For example, project clusters will override group clusters.")
+        %strong
+          = link_to _('More information'), help_page_path('user/group/clusters/', anchor: 'cluster-precedence')
+
     .clusters-table.js-clusters-list
       .gl-responsive-table-row.table-row-header{ role: "row" }
         .table-section.section-60{ role: "rowheader" }

locale/gitlab.pot

@@ -1497,6 +1497,9 @@ msgstr ""
 msgid "ClusterIntegration|Choose which of your environments will use this cluster."
 msgstr ""
 
+msgid "ClusterIntegration|Clusters are utilized by selecting the nearest ancestor with a matching environment scope. For example, project clusters will override group clusters."
+msgstr ""
+
 msgid "ClusterIntegration|Copy API URL"
 msgstr ""