Add datetime type to deployed_before and deployed_after API params

What is this about?

As discussed in !213476 (comment 2922888597), deployed_after and deployed_before params should have type: DateTime to handle param validations, but it would fail currently if we add types now due to the custom parsing logic

Potential Fixes

• Set type: DateTime to those params and return early if the param is already DateTime
• Confirm if the custom parsing logic is still required. If not, we should just be able to set type: DateTime once the custom logic is removed.

Related to

• !213476 (comment 2925016814)