… error on update when priority is not set or 0
Reference: #17871
Priority is optional, but it is currently configured in every test configuration which is why this was not found before. To minimize the changes to verify this bug and timebox effort as part of triage, submitting one preferred style test that covers the behavior.
Previously:
```
=== CONT TestAccAWSSSMMaintenanceWindowTask_Description
resource_aws_ssm_maintenance_window_task_test.go:114: Step 3/3 error: Error running apply: exit status 1
Error: Error updating Maintenance Window (mw-02f66f1bc3df08b83) Task (4c1a1e3e-c449-4e2d-882c-5f8a23a2104d): ValidationException: Value null at 'Priority' failed to satisfy constraint: Member must not be null
status code: 400, request id: fc15f736-7e53-49bb-8d5d-11f35ba98a30
on terraform_plugin_test.tf line 58, in resource "aws_ssm_maintenance_window_task" "test":
58: resource "aws_ssm_maintenance_window_task" "test" {
--- FAIL: TestAccAWSSSMMaintenanceWindowTask_Description (22.29s)
```
Output from acceptance testing in AWS Commercial:
```
--- PASS: TestAccAWSSSMMaintenanceWindowTask_basic (36.64s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_Description (36.65s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_disappears (20.12s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_emptyNotificationConfig (21.04s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_noRole (21.13s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationAutomationParameters (49.73s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationLambdaParameters (39.99s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationRunCommandParameters (50.76s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationRunCommandParametersCloudWatch (53.64s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationStepFunctionParameters (23.05s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_updateForcesNewResource (36.64s)
```
Output from acceptance testing in AWS GovCloud (US):
```
--- PASS: TestAccAWSSSMMaintenanceWindowTask_basic (48.68s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_Description (45.57s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_disappears (28.64s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_emptyNotificationConfig (28.72s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_noRole (28.97s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationAutomationParameters (52.58s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationLambdaParameters (49.44s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationRunCommandParameters (54.30s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationRunCommandParametersCloudWatch (60.93s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_TaskInvocationStepFunctionParameters (31.03s)
--- PASS: TestAccAWSSSMMaintenanceWindowTask_updateForcesNewResource (46.25s)
```