Fix typos in Input and Local Variables guide (hashicorp#8741)

website/source/guides/hcl/variables/index.html.md.erb

@@ -41,8 +41,8 @@ two have empty blocks `{}`. The third sets a default. If a default value is
 set, the variable is optional. Otherwise, the variable is required.
 This also defines two locals: `debian_ami_name` and `foo`.
 
--> **Note**: that it is *not* possible to use variables in a variable defintion
-but it *is* possible to use locals and variables in a local definintion.
+-> **Note**: that it is *not* possible to use variables in a variable definition
+but it *is* possible to use locals and variables in a local definition.
 
 ## Using Variables and locals in Configuration