update docstring (#9617)

website/pages/docs/builders/amazon/chroot.mdx

@@ -131,7 +131,8 @@ Here is a basic example. It is completely valid except for the access keys:
 // set the environment variables to have the same name as the declared
 // variables, with the prefix PKR_VAR_.
 
-// You could also hardcode them into the file, but we recommend against that.
+// There are other ways to [set variables](/docs/from-1.5/variables#assigning-values-to-build-variables), including from a var
+// file or as a command argument.
 
 // export PKR_VAR_aws_access_key=$YOURKEY
 variable "aws_access_key" {

website/pages/docs/builders/amazon/ebs.mdx

@@ -147,7 +147,8 @@ run:
 // set the environment variables to have the same name as the declared
 // variables, with the prefix PKR_VAR_.
 
-// You could also hardcode them into the file, but we recommend against that.
+// There are other ways to [set variables](/docs/from-1.5/variables#assigning-values-to-build-variables)
+// including from a var file or as a command argument.
 
 // export PKR_VAR_aws_access_key=$YOURKEY
 variable "aws_access_key" {