Consolidate queue_adapter= and interpret_adapter

Since #25037, `queue_adapter=` simply delegates to `interpret_adapter`
only.

activejob/lib/active_job/queue_adapter.rb

@@ -29,28 +29,22 @@ def queue_adapter_name
       # Specify the backend queue provider. The default queue adapter
       # is the +:async+ queue. See QueueAdapters for more
       # information.
-      def queue_adapter=(name_or_adapter_or_class)
-        interpret_adapter(name_or_adapter_or_class)
-      end
-
-      private
-
-        def interpret_adapter(name_or_adapter_or_class)
-          case name_or_adapter_or_class
-          when Symbol, String
-            assign_adapter(name_or_adapter_or_class.to_s,
-                           ActiveJob::QueueAdapters.lookup(name_or_adapter_or_class).new)
+      def queue_adapter=(name_or_adapter)
+        case name_or_adapter
+        when Symbol, String
+          queue_adapter = ActiveJob::QueueAdapters.lookup(name_or_adapter).new
+          assign_adapter(name_or_adapter.to_s, queue_adapter)
+        else
+          if queue_adapter?(name_or_adapter)
+            adapter_name = "#{name_or_adapter.class.name.demodulize.remove('Adapter').underscore}"
+            assign_adapter(adapter_name, name_or_adapter)
           else
-            if queue_adapter?(name_or_adapter_or_class)
-              adapter_name = "#{name_or_adapter_or_class.class.name.demodulize.remove('Adapter').underscore}"
-              assign_adapter(adapter_name,
-                             name_or_adapter_or_class)
-            else
-              raise ArgumentError
-            end
+            raise ArgumentError
           end
         end
+      end
 
+      private
         def assign_adapter(adapter_name, queue_adapter)
           self._queue_adapter_name = adapter_name
           self._queue_adapter = queue_adapter