Ensure generic enqueuer is reset correctly (#4258)

Author: johha

spec/unit/jobs/generic_enqueuer_spec.rb

@@ -21,7 +21,7 @@ def perform
 
     before do
       # Reset singleton instance to ensure clean tests
-      Thread.current[:generic_enqueuer] = nil
+      GenericEnqueuer.reset!
     end
 
     describe '.shared' do

spec/unit/jobs/reoccurring_job_spec.rb

@@ -73,6 +73,8 @@ def perform
       it 'keeps the delayed job\'s priority when re-enqueuing' do
         TestConfig.config[:jobs][:priorities] = { 'fake-job': 20 }
 
+        Jobs::GenericEnqueuer.reset! # Ensure no previous state interferes
+
         pollable_job = Jobs::Enqueuer.new({ queue: Jobs::Queues.generic, priority: 22 }).enqueue_pollable(FakeJob.new)
         expect(Delayed::Job.where(guid: PollableJobModel.first.delayed_job_guid).first[:priority]).to eq(42)