Change manage events metric counter method

Underlying relation 'events' for
usage_activity_by_stage_monthly.manage.events has to many records
which cause ordinary batch counter to reject query due to surpassed
limits. Estimated batch counter has higher max limits, so
replacing ordinary batch counter with estimated one should address
the problem

Changelog: fixed

lib/gitlab/usage_data.rb

@@ -536,7 +536,9 @@ module Gitlab
       # rubocop: disable CodeReuse/ActiveRecord
       def usage_activity_by_stage_manage(time_period)
         {
-          events: distinct_count(::Event.where(time_period), :author_id),
+          # rubocop: disable UsageData/LargeTable
+          events: estimate_batch_distinct_count(::Event.where(time_period), :author_id),
+          # rubocop: enable UsageData/LargeTable
           groups: distinct_count(::GroupMember.where(time_period), :user_id),
           users_created: count(::User.where(time_period), start: minimum_id(User), finish: maximum_id(User)),
           omniauth_providers: filtered_omniauth_provider_names.reject { |name| name == 'group_saml' },

spec/lib/gitlab/usage_data_spec.rb

@@ -193,6 +193,8 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
   end
 
   describe 'usage_activity_by_stage_manage' do
+    let_it_be(:error_rate) { Gitlab::Database::PostgresHll::BatchDistinctCounter::ERROR_RATE }
+
     it 'includes accurate usage_activity_by_stage data' do
       stub_config(
         omniauth:
@@ -213,14 +215,14 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
       end
 
       expect(described_class.usage_activity_by_stage_manage({})).to include(
-        events: 2,
+        events: be_within(error_rate).percent_of(2),
         groups: 2,
         users_created: 6,
         omniauth_providers: ['google_oauth2'],
         user_auth_by_provider: { 'group_saml' => 2, 'ldap' => 4, 'standard' => 0, 'two-factor' => 0, 'two-factor-via-u2f-device' => 0, "two-factor-via-webauthn-device" => 0 }
       )
       expect(described_class.usage_activity_by_stage_manage(described_class.monthly_time_range_db_params)).to include(
-        events: 1,
+        events: be_within(error_rate).percent_of(1),
         groups: 1,
         users_created: 3,
         omniauth_providers: ['google_oauth2'],