Revert prisma create-new-database-in-existing-project action to upstream master version

Author: Nauxie

components/prisma_management_api/actions/create-new-database-in-existing-project/create-new-database-in-existing-project.mjs

@@ -36,14 +36,16 @@ export default {
     if (!this.region) {
       throw new Error("Region is required for creating a database");
     }
+    
+    const data = {
+      region: this.region,
+    };
+    if (this.isDefault !== undefined) data.default = this.isDefault;
 
     const response = await this.app.createDatabase({
       $,
       projectId: this.projectId,
-      data: {
-        region: this.region,
-        default: this.isDefault,
-      },
+      data,
     });
 
     if (response) {