Adds 'AWSSupportAccess' Policy to mdr_terraformer

CIS 1.20 requires "Ensure a support role has been created to manage
incidents with AWS support".

While the mdr_terraformer role already has this access, an explicit
policy attachment is required in order to correctly trigger the
config rule.

To be tagged v0.7.8

submodules/iam/child_account_roles/role-mdr_terraformer.tf

@@ -9,3 +9,8 @@ resource aws_iam_role_policy_attachment "mdr_terraformer-mdr_terraformer" {
   role       = aws_iam_role.mdr_terraformer.name 
   policy_arn = module.standard_iam_policies.arns["mdr_terraformer"]
 }
+
+resource aws_iam_role_policy_attachment "mdr_terraformer-AWSSupportAccess" {
+  role       = aws_iam_role.mdr_terraformer.name
+  policy_arn = "arn:${data.aws_partition.current.partition}:iam::aws:policy/AWSSupportAccess"
+}

submodules/iam/common_services_roles/role-mdr_terraformer.tf

@@ -9,3 +9,8 @@ resource aws_iam_role_policy_attachment "mdr_terraformer-mdr_terraformer" {
   role       = aws_iam_role.mdr_terraformer.name 
   policy_arn = module.standard_iam_policies.arns["mdr_terraformer"]
 }
+
+resource aws_iam_role_policy_attachment "mdr_terraformer-AWSSupportAccess" {
+  role       = aws_iam_role.mdr_terraformer.name 
+  policy_arn = "arn:${data.aws_partition.current.partition}:iam::aws:policy/AWSSupportAccess"
+}