feat(cron-jobs): conditionally enable recurring tasks based on environment variable

- Updated the cron job initialization to start recurring tasks only if the ENABLE_RECURRING_JOBS environment variable is set to "true". This allows for more flexible job management based on deployment configurations.

worklenz-backend/src/cron_jobs/index.ts

@@ -7,5 +7,5 @@ export function startCronJobs() {
   startNotificationsJob();
   startDailyDigestJob();
   startProjectDigestJob();
-  startRecurringTasksJob();
+  if (process.env.ENABLE_RECURRING_JOBS === "true") startRecurringTasksJob();
 }