Make run_after optional as part of API for Trigger Dag Run

[sunank200]

Currently run_after is defaulted to timezone.utcnow() in API. Now it is changed to optional with values - data_interval_end or utcnow() in the logic.

closes: #46650

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[bugraoz93]

Looks good!

[pierrejeambrun]

I'll just mark it as 'request change' so we don't merge this by mistake because this will cause troubles on the UI in its current state.

The UI needs a non nullable date to work. before it was logical_date and a lot of things broke when we did the AIP-83 amendment.

To resolve that we agreed on using the run_after date because it's not supposed to be null. This will bring trouble on the UI side if this change go through, is that required, should we use another non nullable date for the UI ?

[bbovenzi]

Can you update the title and description of this PR to say its for Trigger Dag Run? I was worried we were making it nullable everywhere for a second.

disregard

[pierrejeambrun]

Can you update the title and description of this PR to say its for Trigger Dag Run? I was worried we were making it nullable everywhere for a second.

I got confused too, disregard my previous comment, that's just for the Trigger API, looks good thanks.

[pierrejeambrun]

Looks good.

[sunank200]

Can you update the title and description of this PR to say its for Trigger Dag Run? I was worried we were making it nullable everywhere for a second.

Changed it. I should have been more clear in my title.