CCM-13476: add todo for generating event source

Author: Ian-Hodges

lambdas/print-status-handler/src/apis/sqs-handler.ts

@@ -101,6 +101,7 @@ function generateUpdatedEvent(event: LetterEvent): PrintLetterTransitioned {
     dataschema:
       'https://notify.nhs.uk/cloudevents/schemas/digital-letters/2025-10-draft/data/digital-letters-print-letter-transitioned-data.schema.json',
     type: 'uk.nhs.notify.digital.letters.print.letter.transitioned.v1',
+    // TODO: CCM-13892 Generate event digital letters source property from scratch
     source:
       '/nhs/england/notify/production/primary/data-plane/digitalletters/print',
     data: {