Add missing ENABLE_FREEZE variable used to decide on cron job inclusion (#119)

Actually include the `ENABLE_FREEZE` variable used as conditional for the cron job installation.

Author: jonasbardino

Dockerfile.rocky8

@@ -1463,6 +1463,7 @@ ARG ENABLE_GDP
 ARG WITH_GIT
 ARG MIG_GIT_BRANCH
 ARG ENABLE_QUOTA
+ARG ENABLE_FREEZE
 ARG QUOTA_BACKEND
 ARG QUOTA_LUSTRE_VERSION
 ARG OS_CA_CERT_SOURCE_PATH

Dockerfile.rocky9

@@ -1352,6 +1352,7 @@ ARG ENABLE_GDP
 ARG WITH_GIT
 ARG MIG_GIT_BRANCH
 ARG ENABLE_QUOTA
+ARG ENABLE_FREEZE
 ARG QUOTA_BACKEND
 ARG QUOTA_LUSTRE_VERSION
 ARG OS_CA_CERT_SOURCE_PATH