chore: print getClass() in CodegenException

Author: trivikr

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/CodegenUtils.java

@@ -162,8 +162,8 @@ static List<String> getFunctionParametersList(Map<String, Object> paramsMap) {
                     functionParametersList.add(String.format("%s: '%s'", key, value));
                 } else {
                     // Future support for param type should be added in else if.
-                    throw new CodegenException("plugin function parameters not supported for type"
-                            + value.toString());
+                    throw new CodegenException("Plugin function parameters not supported for type "
+                            + value.getClass());
                 }
             }
         }