fix: Eliminates null check on tag values to fix for_each error about …

…unknown *keys* (#3119)

Eliminates null check on tag values to fix for_each error about unknown *keys*

Fixes #3118

Related #2760 
Related #2681 
Related #2337

main.tf

@@ -124,7 +124,7 @@ resource "aws_ec2_tag" "cluster_primary_security_group" {
   # Ref: https://github.com/terraform-aws-modules/terraform-aws-eks/pull/2006
   # Ref: https://github.com/terraform-aws-modules/terraform-aws-eks/pull/2008
   for_each = { for k, v in merge(var.tags, var.cluster_tags) :
-    k => v if local.create && k != "Name" && var.create_cluster_primary_security_group_tags && v != null
+    k => v if local.create && k != "Name" && var.create_cluster_primary_security_group_tags
   }
 
   resource_id = aws_eks_cluster.this[0].vpc_config[0].cluster_security_group_id