removed hard coded product version

Author: jldohmann

modules/ipi-install-retrieving-the-openshift-installer.adoc

@@ -9,8 +9,8 @@
 Use the `stable-4.x` version of the installer to deploy the generally
 available stable version of {product-title}:
 
-[source,terminal]
+[source,terminal,subs="attributes"]
 ----
-$ export VERSION=stable-4.10
+$ export VERSION=stable-{product-version}
 export RELEASE_IMAGE=$(curl -s https://mirror.openshift.com/pub/openshift-v4/clients/ocp/$VERSION/release.txt | grep 'Pull From: quay.io' | awk -F ' ' '{print $3}')
 ----