Swift syntax fix

Author: abnegate

templates/swift/base/params.twig

@@ -10,7 +10,7 @@
         {%- else -%} let
         {%- endif %} params: [String: Any?] = [
         {%~ for parameter in method.parameters.query | merge(method.parameters.body) %}
-            "{{ parameter.name }}": {{ parameter.name | caseCamel | escapeKeyword }}{% if not loop.last %},{% endif %}
+            "{{ parameter.name }}": {{ parameter.name | caseCamel | escapeKeyword }}{% if not loop.last or method.auth | length > 0 %},{% endif %}
 
         {%~ endfor %}
         {%~ if method.auth | length > 0 %}