chore: Remove unnecessary whitespace in JoatuController

Author: rsmithlal

app/controllers/better_together/joatu/joatu_controller.rb

@@ -35,7 +35,7 @@ def joatu_source_class(source_type_param)
 
         # Dynamically build allow-list from models that include the Exchange concern
         valid_source_types = BetterTogether::Joatu::Exchange.included_in_models
-        
+
         valid_source_types.find { |klass| klass.to_s == param_type }
       end
     end