Only process retry queue on manual retries

ruby/lib/minitest/queue/runner.rb

@@ -49,7 +49,8 @@ def retry_command
 
       def run_command
         require_worker_id!
-        if queue.retrying? || retry?
+        # if it's an automatic job retry we should process the main queue
+        if manual_retry?
           if queue.expired?
             abort! "The test run is too old and can't be retried"
           end
@@ -671,9 +672,15 @@ def abort!(message, exit_status=1)
         exit! exit_status # exit! is required to avoid minitest at_exit callback
       end
 
+      def manual_retry?
+        # this env variable only exists on Buildkite so we should default to manual for backward compatibility
+        (retry? || queue.retrying?) &&
+          ENV.fetch('BUILDKITE_RETRY_TYPE', 'manual') == 'manual'
+      end
+
       def retry?
-        ENV["BUILDKITE_RETRY_COUNT"].to_i > 0 ||
-          ENV["SEMAPHORE_PIPELINE_RERUN"] == "true"
+        ENV['BUILDKITE_RETRY_COUNT'].to_i > 0 ||
+          ENV['SEMAPHORE_PIPELINE_RERUN'] == 'true'
       end
     end
   end