Remove calculateRequestOrder Function and fix bug

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/K6ClientCodegen.java

@@ -707,10 +707,8 @@ public void preprocessOpenAPI(OpenAPI openAPI) {
                 Optional<DataExtractSubstituteParameter> dataExtract = getDataExtractSubstituteParameter(
                         dataExtractSubstituteParams, operationId);
 
-                // calculate order for this current request
-                Integer requestOrder = calculateRequestOrder(operationGroupingOrder, requests.size());
-
-                requests.put(requestOrder, new HTTPRequest(
+                // create requests
+                requests.putIfAbsent(requests.size(), new HTTPRequest(
                     operationId,
                     method.toString().toLowerCase(Locale.ROOT),
                     path,
@@ -933,7 +931,7 @@ private void addOrUpdateRequestGroup(Map<String, HTTPRequestGroup> requestGroups
             existingHTTPRequestGroup.addRequests(requests);
             existingHTTPRequestGroup.addVariables(variables);
         } else {
-            requestGroups.put(groupName, new HTTPRequestGroup(groupName, variables, requests));
+            requestGroups.putIfAbsent(groupName, new HTTPRequestGroup(groupName, variables, requests));
         }
     }
 
@@ -1127,36 +1125,6 @@ private void extractRequestBodyExample(RequestBody requestBody, String contentTy
         }
     }
 
-    /**
-     * Calculate order for this current request
-     *
-     * @param operationGroupingOrder
-     * @param requestsSize
-     * @return request order
-     */
-    private Integer calculateRequestOrder(OptionalInt operationGroupingOrder, int requestsSize) {
-        int requestOrder;
-
-        if (operationGroupingOrder.isPresent()) {
-            requestOrder = operationGroupingOrder.getAsInt() - 1;
-
-        } else {
-            switch (requestsSize) {
-                case 0:
-                case 1:
-                    requestOrder = requestsSize;
-                    break;
-
-                default:
-                    requestOrder = (requestsSize - 1);
-                    break;
-            }
-        }
-
-        return requestOrder;
-    }
-
-    //
 
     /**
      * Any variables not defined yet but used for subsequent data extraction must be