Add missing spec for recording unique events

Properly test unique events recorded on shared
examples.

ee/spec/lib/gitlab/usage_data_counters/epic_activity_unique_counter_spec.rb

@@ -296,7 +296,7 @@ RSpec.describe Gitlab::UsageDataCounters::EpicActivityUniqueCounter, :clean_gitl
     end
 
     it_behaves_like 'a daily tracked issuable event' do
-      let(:action) { described_class::ISSUE_EPIC_DESTROYED }
+      let(:action) { described_class::EPIC_DESTROYED }
     end
 
     it_behaves_like 'does not track when feature flag is disabled', :track_epics_activity

spec/support/shared_examples/lib/gitlab/usage_data_counters/issuable_activity_shared_examples.rb

@@ -5,7 +5,7 @@ RSpec.shared_examples 'a daily tracked issuable event' do
     stub_application_setting(usage_ping_enabled: true)
   end
 
-  def count_unique(date_from:, date_to:)
+  def count_unique(date_from: 1.minute.ago, date_to: 1.minute.from_now)
     Gitlab::UsageDataCounters::HLLRedisCounter.unique_events(event_names: action, start_date: date_from, end_date: date_to)
   end
 
@@ -14,6 +14,7 @@ RSpec.shared_examples 'a daily tracked issuable event' do
       expect(track_action(author: user1)).to be_truthy
       expect(track_action(author: user1)).to be_truthy
       expect(track_action(author: user2)).to be_truthy
+      expect(count_unique).to eq(2)
     end
   end