fix: remove deprecated hashicorp/template provider

- in m1 macos, cannot initialize eks-blue/green stacks in the
  blue-green-upgrade pattern
```sh
$ cd patterns/eks-blue-green-upgrade/eks-blue
$ terraform init
...
╷
│ Error: Incompatible provider version
│
│ Provider registry.terraform.io/hashicorp/template v2.2.0 does not have a package available for your current platform, darwin_arm64.
│
│ Provider releases are separate from Terraform CLI releases, so not all providers are available for all platforms. Other versions of this
│ provider may have different platforms supported.
╵
```
- the hashicorp/template provider is deprecated
  and not supported in m1 macos
  - ref. https://discuss.hashicorp.com/t/template-v2-2-0-does-not-have-a-package-available-mac-m1/35099
- also the provider is not used in the module
  - it seems was added at #1769(2e09cf8) for debugging
  - the output for debugging is commented out; not used
- removed deprecated, unused hashicorp/template provider
- removed the comments in output

Signed-off-by: flavono123 <[email protected]>

patterns/blue-green-upgrade/modules/eks_cluster/outputs.tf

@@ -49,10 +49,3 @@ output "gitops_metadata" {
   value       = local.addons_metadata
   sensitive   = true
 }
-
-# output "debug" {
-#   description = "debug output"
-#   #value = data.template_file.addons_template.rendered
-#   value = data.template_file.workloads_template.rendered
-#   #value = file("${path.module}/../../bootstrap/addons.yaml")
-# }

patterns/blue-green-upgrade/modules/eks_cluster/versions.tf

@@ -11,9 +11,5 @@ terraform {
       source  = "hashicorp/kubernetes"
       version = "2.22.0"
     }
-    template = {
-      source  = "hashicorp/template"
-      version = ">= 2.2.0"
-    }
   }
 }