Fix design counters for Geo Node status

We do inner join of projects and designs
If there are few designs we will get project duplicates so we add
destinct here

ee/app/finders/geo/design_registry_finder.rb

@@ -3,7 +3,7 @@
 module Geo
   class DesignRegistryFinder < RegistryFinder
     def count_syncable
-      designs_repositories.count
+      GeoNode.find(current_node_id).projects.count_designs
     end
 
     def count_synced
@@ -22,12 +22,10 @@ module Geo
 
     private
 
-    def designs_repositories
-      current_node.projects.inner_join_design_management
-    end
-
     def registries
-      designs_repositories
+      current_node
+        .projects
+        .inner_join_design_management
         .inner_join_design_registry
     end
   end

ee/app/models/ee/project.rb

@@ -191,6 +191,19 @@ module EE
         joins('LEFT JOIN services ON services.project_id = projects.id AND services.type = \'GitlabSlackApplicationService\' AND services.active IS true')
           .where('services.id IS NULL')
       end
+
+      def inner_join_design_management
+        join_statement =
+          arel_table
+            .join(DesignManagement::Design.arel_table, Arel::Nodes::InnerJoin)
+            .on(arel_table[:id].eq(DesignManagement::Design.arel_table[:project_id]))
+
+        joins(join_statement.join_sources)
+      end
+
+      def count_designs
+        inner_join_design_management.distinct.count
+      end
     end
 
     def can_store_security_reports?

ee/spec/finders/geo/design_registry_finder_spec.rb

@@ -21,7 +21,10 @@ describe Geo::DesignRegistryFinder, :geo, :geo_fdw do
 
   context 'count all the things' do
     describe '#count_syncable' do
-      it 'returns number of container repositories' do
+      it 'returns number of design repositories' do
+        # One more design for the same project to assert absence of duplicates
+        create(:design, project: synced_registry.project)
+
         result = subject.count_syncable
 
         expect(result).to eq(2)
@@ -67,7 +70,7 @@ describe Geo::DesignRegistryFinder, :geo, :geo_fdw do
 
       context 'count all the things' do
         describe '#count_syncable' do
-          it 'returns number of container repositories' do
+          it 'returns number of design repositories' do
             result = subject.count_syncable
 
             expect(result).to eq(2)