Add policy for Group Activity Analytics feature

The policy is set per group.

This also adds license for the feature for EE Starter/
Bronze users

ee/app/models/license.rb

@@ -17,6 +17,7 @@ class License < ApplicationRecord
     description_diffs
     elastic_search
     export_issues
+    group_activity_analytics
     group_bulk_edit
     group_burndown_charts
     group_webhooks

ee/app/policies/ee/group_policy.rb

@@ -18,6 +18,10 @@ module EE
         @subject.feature_available?(:cycle_analytics_for_groups)
       end
 
+      condition(:group_activity_analytics_available) do
+        @subject.feature_available?(:group_activity_analytics)
+      end
+
       condition(:can_owners_manage_ldap, scope: :global) do
         ::Gitlab::CurrentSettings.allow_group_owners_to_manage_ldap?
       end
@@ -78,6 +82,9 @@ module EE
       rule { can?(:read_group) & contribution_analytics_available }
         .enable :read_group_contribution_analytics
 
+      rule { can?(:read_group) & group_activity_analytics_available }
+        .enable :read_group_activity_analytics
+
       rule { reporter & cycle_analytics_available }.policy do
         enable :read_group_cycle_analytics, :create_group_stage, :read_group_stage, :update_group_stage, :delete_group_stage
       end

ee/spec/policies/group_policy_spec.rb

@@ -61,6 +61,26 @@ describe GroupPolicy do
     it { is_expected.not_to be_allowed(:read_group_contribution_analytics) }
   end
 
+  context 'when group activity analytics is available' do
+    let(:current_user) { developer }
+
+    before do
+      stub_licensed_features(group_activity_analytics: true)
+    end
+
+    it { is_expected.to be_allowed(:read_group_activity_analytics) }
+  end
+
+  context 'when group activity analytics is not available' do
+    let(:current_user) { developer }
+
+    before do
+      stub_licensed_features(group_activity_analytics: false)
+    end
+
+    it { is_expected.not_to be_allowed(:read_group_activity_analytics) }
+  end
+
   context 'when timelogs report feature is enabled' do
     before do
       stub_licensed_features(group_timelogs: true)