fix: define handlebar json extension

Signed-off-by: Pranav C <pranavxc@gmail.com>

packages/nocodb-nest/src/helpers/webhookHelpers.ts

@@ -5,6 +5,10 @@ import NcPluginMgrv2 from './NcPluginMgrv2';
 import type { Column, FormView, Hook, Model, View } from '../models';
 import type { HookLogType } from 'nocodb-sdk';
 
+Handlebars.registerHelper('json', function (context) {
+  return JSON.stringify(context);
+});
+
 export function parseBody(template: string, data: any): string {
   if (!template) {
     return template;