Remove the :sidekiq metadata as it's not needed anymore

Signed-off-by: Rémy Coutable <remy@rymai.me>

ee/spec/tasks/gitlab/seed/group_seed_rake_spec.rb

@@ -2,7 +2,7 @@
 
 require 'rake_helper'
 
-describe 'gitlab:seed:group_seed rake task', :sidekiq do
+describe 'gitlab:seed:group_seed rake task' do
   let(:username) { 'group_seed' }
   let!(:user) { create(:user, username: username) }
   let(:task_params) { [2, username] }

spec/migrations/20200130145430_reschedule_migrate_issue_trackers_data_spec.rb

@@ -3,7 +3,7 @@
 require 'spec_helper'
 require Rails.root.join('db', 'post_migrate', '20200130145430_reschedule_migrate_issue_trackers_data.rb')
 
-describe RescheduleMigrateIssueTrackersData, :migration, :sidekiq do
+describe RescheduleMigrateIssueTrackersData, :migration do
   let(:services) { table(:services) }
   let(:migration_class) { Gitlab::BackgroundMigration::MigrateIssueTrackersSensitiveData }
   let(:migration_name)  { migration_class.to_s.demodulize }

spec/migrations/schedule_update_existing_subgroup_to_match_visibility_level_of_parent_spec.rb

@@ -3,7 +3,7 @@
 require 'spec_helper'
 require Rails.root.join('db', 'post_migrate', '20200110121314_schedule_update_existing_subgroup_to_match_visibility_level_of_parent.rb')
 
-describe ScheduleUpdateExistingSubgroupToMatchVisibilityLevelOfParent, :migration, :sidekiq do
+describe ScheduleUpdateExistingSubgroupToMatchVisibilityLevelOfParent, :migration do
   include MigrationHelpers::NamespacesHelpers
   let(:migration_class) { described_class::MIGRATION }
   let(:migration_name)  { migration_class.to_s.demodulize }

spec/tasks/gitlab/seed/group_seed_rake_spec.rb

@@ -2,7 +2,7 @@
 
 require 'rake_helper'
 
-describe 'gitlab:seed:group_seed rake task', :sidekiq do
+describe 'gitlab:seed:group_seed rake task' do
   let(:username) { 'group_seed' }
   let!(:user) { create(:user, username: username) }
   let(:task_params) { [2, username] }