Add checks to rename processor for the message field for the Observability Beats Modules

[ishleenk17]

As a follow up to this ticket : #7822
We should add the null and ignore_missing flag checks to rename processors for event.original field to the corresponding beats modules as well. As the same issue can be observed in the beats as well.

Current state:

rename:
field: message
target_field: event.original
Expected State:

rename:
field: message
target_field: event.original
ignore_missing: true
if: 'ctx.event?.original == null'
description: 'Renames the original message field to event.original to store a copy of the original message. The event.original field is not touched if the document already has one; it may happen when Logstash sends the document.'

We should first list down all the beats modules that need the changes and then progress with the change.

[lalit-satapathy]

Looks duplicate of elastic/beats#38224 ?

[ishleenk17]

Looks duplicate of elastic/beats#38224 ?

Yes, these are duplicates