Adding pure_repos to the AIO model

* This patch is used as workaround solution for one of
the cases covered by PROD-14299

* In case of needed "purge_repos: true" will be passed through SALT_OVERRIDES
in jenkins job

Change-Id: I84478c17fd112bf48eafeff1f20885467d3b0e8f
diff --git a/classes/cluster/virtual-mcp11-aio/infra/config.yml b/classes/cluster/virtual-mcp11-aio/infra/config.yml
index ec91ce4..c59029b 100644
--- a/classes/cluster/virtual-mcp11-aio/infra/config.yml
+++ b/classes/cluster/virtual-mcp11-aio/infra/config.yml
@@ -7,3 +7,4 @@
     system:
       name: cfg01
       domain: ${_param:cluster_domain}
+      purge_repos: ${_param:linux_system_purge_repos}