feat: Allow users to specify default launch template name in node groups (terraform-aws-modules#1946)

Author: bryantbiggs

node_groups.tf

@@ -273,7 +273,7 @@ module "eks_managed_node_group" {
 
   # Launch Template
   create_launch_template          = try(each.value.create_launch_template, var.eks_managed_node_group_defaults.create_launch_template, true)
-  launch_template_name            = try(each.value.launch_template_name, each.key)
+  launch_template_name            = try(each.value.launch_template_name, var.eks_managed_node_group_defaults.launch_template_name, each.key)
   launch_template_use_name_prefix = try(each.value.launch_template_use_name_prefix, var.eks_managed_node_group_defaults.launch_template_use_name_prefix, true)
   launch_template_version         = try(each.value.launch_template_version, var.eks_managed_node_group_defaults.launch_template_version, null)
   launch_template_description     = try(each.value.launch_template_description, var.eks_managed_node_group_defaults.launch_template_description, "Custom launch template for ${try(each.value.name, each.key)} EKS managed node group")
@@ -393,7 +393,7 @@ module "self_managed_node_group" {
 
   # Launch Template
   create_launch_template          = try(each.value.create_launch_template, var.self_managed_node_group_defaults.create_launch_template, true)
-  launch_template_name            = try(each.value.launch_template_name, each.key)
+  launch_template_name            = try(each.value.launch_template_name, var.self_managed_node_group_defaults.launch_template_name, each.key)
   launch_template_use_name_prefix = try(each.value.launch_template_use_name_prefix, var.self_managed_node_group_defaults.launch_template_use_name_prefix, true)
   launch_template_version         = try(each.value.launch_template_version, var.self_managed_node_group_defaults.launch_template_version, null)
   launch_template_description     = try(each.value.launch_template_description, var.self_managed_node_group_defaults.launch_template_description, "Custom launch template for ${try(each.value.name, each.key)} self managed node group")