feat: allow ecs service changes (e.g. image updates) (#39)

## Description
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## Motivation and Context
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## Breaking Changes
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## How Has This Been Tested?
- [ ] I have updated at least one of the `examples/*` to demonstrate and
validate my change(s)
- [ ] I have tested and validated these changes using one or more of the
provided `examples/*` projects
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README.md

@@ -51,6 +51,7 @@
 | <a name="input_environment"></a> [environment](#input\_environment) | ID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT' | `string` | `null` | no |
 | <a name="input_environment_variables"></a> [environment\_variables](#input\_environment\_variables) | The environment variables to pass to the container. This is a map of string: {key: value}. map\_environment overrides environment | `map(string)` | `null` | no |
 | <a name="input_id_length_limit"></a> [id\_length\_limit](#input\_id\_length\_limit) | Limit `id` to this many characters (minimum 6).<br>Set to `0` for unlimited length.<br>Set to `null` for keep the existing setting, which defaults to `0`.<br>Does not affect `id_full`. | `number` | `null` | no |
+| <a name="input_ignore_changes_task_definition"></a> [ignore\_changes\_task\_definition](#input\_ignore\_changes\_task\_definition) | Whether to ignore changes in container definition and task definition in the ECS service | `bool` | `false` | no |
 | <a name="input_label_key_case"></a> [label\_key\_case](#input\_label\_key\_case) | Controls the letter case of the `tags` keys (label names) for tags generated by this module.<br>Does not affect keys of tags passed in via the `tags` input.<br>Possible values: `lower`, `title`, `upper`.<br>Default value: `title`. | `string` | `null` | no |
 | <a name="input_label_order"></a> [label\_order](#input\_label\_order) | The order in which the labels (ID elements) appear in the `id`.<br>Defaults to ["namespace", "environment", "stage", "name", "attributes"].<br>You can omit any of the 6 labels ("tenant" is the 6th), but at least one must be present. | `list(string)` | `null` | no |
 | <a name="input_label_orders"></a> [label\_orders](#input\_label\_orders) | Overrides the `labels_order` for the different labels to modify ID elements appear in the `id` | <pre>object({<br>    cloudwatch = optional(list(string)),<br>    ecs        = optional(list(string)),<br>    iam        = optional(list(string)),<br>    vpc        = optional(list(string))<br>  })</pre> | `{}` | no |

main.tf

@@ -151,13 +151,14 @@ module "ecs_service_task" {
   source  = "justtrackio/ecs-alb-service-task/aws"
   version = "1.0.0"
 
-  container_definition_json = "[${module.node_exporter_definition.json_map_encoded},${module.cadvisor_definition.json_map_encoded}]"
-  ecs_cluster_arn           = var.ecs_cluster_arn
-  launch_type               = "EC2"
-  scheduling_strategy       = "DAEMON"
-  task_cpu                  = var.task_cpu
-  task_memory               = var.task_memory
-  network_mode              = "host"
+  container_definition_json      = "[${module.node_exporter_definition.json_map_encoded},${module.cadvisor_definition.json_map_encoded}]"
+  ecs_cluster_arn                = var.ecs_cluster_arn
+  ignore_changes_task_definition = var.ignore_changes_task_definition
+  launch_type                    = "EC2"
+  scheduling_strategy            = "DAEMON"
+  task_cpu                       = var.task_cpu
+  task_memory                    = var.task_memory
+  network_mode                   = "host"
   docker_volumes = [
     {
       host_path                   = "/"

variables.tf

@@ -39,6 +39,12 @@ variable "environment_variables" {
   default     = null
 }
 
+variable "ignore_changes_task_definition" {
+  type        = bool
+  description = "Whether to ignore changes in container definition and task definition in the ECS service"
+  default     = false
+}
+
 variable "label_orders" {
   type = object({
     cloudwatch = optional(list(string)),