[SVC-803 1/N] Add nonpreemptible field to SchedulerPlacement proto

[eggag32]

Adds a nonpreemptible boolean to SchedulerPlacement in modal_proto/api.proto.

This SchedulerPlacement is part of the function definition and is how the client indicates the Function's containers should be scheduled onto nonpreemptible instances.

Checklists

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Compatibility checklist

• Client+Server: this change is compatible with old servers
• Client forward compatibility: this change ensures client can accept data intended for later versions of itself

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[!NOTE]
Adds a nonpreemptible boolean to SchedulerPlacement in modal_proto/api.proto.

• Proto definitions:
  • modal_proto/api.proto:
    • SchedulerPlacement: add boolean field nonpreemptible (= 6).

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[devennavani]

@prbot approve @mwaskom

[modal-pr-review-automation]

Approved 👍. @mwaskom will follow-up review this.

[mwaskom]

✅