Merge pull request GoogleCloudPlatform#4430 from samskillman/fix/spot-instance-config-default

Minimize tf drift for spot instances during re-deploy

Author: samskillman

community/modules/compute/schedmd-slurm-gcp-v6-nodeset/README.md

@@ -210,7 +210,7 @@ modules. For support with the underlying modules, see the instructions in the
 | <a name="input_service_account_email"></a> [service\_account\_email](#input\_service\_account\_email) | Service account e-mail address to attach to the compute instances. | `string` | `null` | no |
 | <a name="input_service_account_scopes"></a> [service\_account\_scopes](#input\_service\_account\_scopes) | Scopes to attach to the compute instances. | `set(string)` | <pre>[<br/>  "https://www.googleapis.com/auth/cloud-platform"<br/>]</pre> | no |
 | <a name="input_shielded_instance_config"></a> [shielded\_instance\_config](#input\_shielded\_instance\_config) | Shielded VM configuration for the instance. Note: not used unless<br/>enable\_shielded\_vm is 'true'.<br/>- enable\_integrity\_monitoring : Compare the most recent boot measurements to the<br/>  integrity policy baseline and return a pair of pass/fail results depending on<br/>  whether they match or not.<br/>- enable\_secure\_boot : Verify the digital signature of all boot components, and<br/>  halt the boot process if signature verification fails.<br/>- enable\_vtpm : Use a virtualized trusted platform module, which is a<br/>  specialized computer chip you can use to encrypt objects like keys and<br/>  certificates. | <pre>object({<br/>    enable_integrity_monitoring = bool<br/>    enable_secure_boot          = bool<br/>    enable_vtpm                 = bool<br/>  })</pre> | <pre>{<br/>  "enable_integrity_monitoring": true,<br/>  "enable_secure_boot": true,<br/>  "enable_vtpm": true<br/>}</pre> | no |
-| <a name="input_spot_instance_config"></a> [spot\_instance\_config](#input\_spot\_instance\_config) | Configuration for spot VMs. | <pre>object({<br/>    termination_action = string<br/>  })</pre> | `null` | no |
+| <a name="input_spot_instance_config"></a> [spot\_instance\_config](#input\_spot\_instance\_config) | Configuration for spot VMs. | <pre>object({<br/>    termination_action = string<br/>  })</pre> | <pre>{<br/>  "termination_action": "STOP"<br/>}</pre> | no |
 | <a name="input_startup_script"></a> [startup\_script](#input\_startup\_script) | Startup script used by VMs in this nodeset | `string` | `"# no-op"` | no |
 | <a name="input_subnetwork_self_link"></a> [subnetwork\_self\_link](#input\_subnetwork\_self\_link) | Subnet to deploy to. | `string` | n/a | yes |
 | <a name="input_tags"></a> [tags](#input\_tags) | Network tag list. | `list(string)` | `[]` | no |

community/modules/compute/schedmd-slurm-gcp-v6-nodeset/variables.tf

@@ -371,7 +371,9 @@ variable "spot_instance_config" {
   type = object({
     termination_action = string
   })
-  default = null
+  default = {
+    termination_action = "STOP"
+  }
 }
 
 variable "bandwidth_tier" {