website: Fix broken markdown style on 'lists' section of variables page (#10944)

website/source/intro/getting-started/variables.html.md

@@ -133,6 +133,7 @@ for the variable.
 ## Lists
 
 Lists are defined either explicitly or implicity
+
 ```
 # implicitly by using brackets [...]
 variable "cidrs" { default = [] }
@@ -142,6 +143,7 @@ variable "cidrs" { type = "list" }
 ```
 
 You can specify lists in a `terraform.tfvars` file:
+
 ```
 cidrs = [ "10.0.0.0/16", "10.1.0.0/16" ]
 ```