Flink: Emit watermarks for the new timestamp_ns and timestamptz_ns types

[pvary]

Feature Request / Improvement

After #9008 is merged, it would be good to add a way to emit watermarks based on the new timestamp columns

Query engine

Flink

[github-actions]

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[pvary]

The #9008 has been merged.
@rodmeneses: would you like to take care of this?

[rodmeneses]

The #9008 has been merged. @rodmeneses: would you like to take care of this?

Sounds good !