Update Vault provider

prod/aws-us-gov/mdr-prod-c2/099-vault-configuration/terragrunt.hcl

@@ -31,7 +31,7 @@ generate "vault-provider" {
   contents  = <<EOF
 #Provider block for Vault. 
 provider "vault" {
-  version = "~> 2.15.0"
+  version = "~> 2.18.0"
   address = "https://${dependency.instance-vault.outputs.vault_alb_address}"
 }
 EOF