Adding Timestamp Extraction to CloudWatch Logs Sink

[MaGonzalMayedo]

Is your feature request related to a problem? Please describe.
Currently the cloudwatch_logs sink publishes log events with the time at which the event is transmitted from the sink. There is no support for extracting an already existing timestamp from the event and using it as the timestamp of the event.

Describe the solution you'd like
A solution would be to extend the current plugin to include a timestamp extraction option. This would be configurable and would allow for the extraction of the timestamp.

Additional context
The timestamp could potentially be extracted in the following way:

• Through a user-entered date configuration. Where the sink would try to pull and use during transmission.
• Through the extraction of a Data-Prepper standard timestamp (via the Date Processor).

Both of these methods would also require the final date to be in UTC prior to being transmitted.