Compute: Add support for FLEX_START and RESERVATION_BOUND provisioning model

[MihajloLinic]

compute: added `FLEX_START` and `RESERVATION_BOUND` support to `google_compute_instance`, `google_compute_instance_template`, and `google_compute_region_instance_template`

This PR adds support for the FLEX_START and RESERVATION_BOUND provisioning models to google_compute_instance, google_compute_instance_template, and google_compute_region_instance_template.

FLEX_START is a VM scheduling option in Google Cloud Compute Engine (part of the Dynamic Workload Scheduler) that allows flexible start times for VM instances, enabling cost optimization by letting Google schedule VM creation within a 24-hour time window. It is specifically designed for accelerator-optimized workloads (GPUs/TPUs).

RESERVATION_BOUND is a VM scheduling option that binds an instance to a specific reservation. When set, the instance will only consume capacity from the targeted reservation (configured via reservation_affinity). This is used with Calendar Reservations (Future Reservations) in the Dynamic Workload Scheduler, where GPU/TPU capacity is pre-booked for a specific time window and delivered as a standard reservation that instances can then target.

Changes

• Schema Updates: Added FLEX_START and RESERVATION_BOUND as valid values for provisioning_model in the scheduling block of instances and instance templates. Updated field descriptions and validation logic.
• TGC Support: Updated Terraform Google Conversion (TGC) logic to ensure FLEX_START and RESERVATION_BOUND are correctly handled during resource conversion.
• Documentation: Updated the resource and data source documentation for instances and templates to include FLEX_START (with its required companion fields like instance_termination_action and max_run_duration) and RESERVATION_BOUND (with its companion reservation_affinity block).
• Tests: Added comprehensive acceptance tests for both provisioning models across all affected resources:
  • TestAccComputeInstance_flexStart, TestAccComputeInstanceTemplate_flexStart, TestAccComputeRegionInstanceTemplate_flexStart
  • TestAccComputeInstance_reservationBound, TestAccComputeInstanceTemplate_reservationBound, TestAccComputeRegionInstanceTemplate_reservationBound

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[github-actions]

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[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 12 files changed, 228 insertions(+), 12 deletions(-))
google-beta provider: Diff ( 12 files changed, 228 insertions(+), 12 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 2 insertions(+), 1 deletion(-))

[modular-magician]

Tests analytics

Total tests: 1389
Passed tests: 1296
Skipped tests: 90
Affected tests: 3

Click here to see the affected service packages

• compute

Action taken

Found 3 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

• TestAccComputeInstanceTemplate_flexStart
• TestAccComputeInstance_flexStart
• TestAccComputeRegionInstanceTemplate_flexStart

Get to know how VCR tests work

[modular-magician]

🟢 Tests passed during RECORDING mode:
TestAccComputeInstanceTemplate_flexStart [Debug log]
TestAccComputeInstance_flexStart [Debug log]
TestAccComputeRegionInstanceTemplate_flexStart [Debug log]

🟢 No issues found for passed tests after REPLAYING rerun.

---

🟢 All tests passed!

View the build log or the debug log for each test

[ScottSuarez]

Can you test what would happen if a user explicitly sets empty string. I think since w are migrating this from another type to essentially an enum we would need to support empty string in the permuations.

[MihajloLinic]

I expanded the scope to include RESERVATION_BOUND option too, implemented in same way the FLEX_START was. I needed them to connect to provision VMs through Coder. I will test empty string after I make sure RESERVATION_BOUND works through Coder