feat: implement mjfilter file for templates (#1244)

* feat: implement mjfilter file for templates

Signed-off-by: Devin Buhl <devin@buhl.casa>

* fix: use data.get in mjfilters

Signed-off-by: Devin Buhl <devin@buhl.casa>

---------

Signed-off-by: Devin Buhl <devin@buhl.casa>

bootstrap/templates/kubernetes/apps/tools/system-upgrade-controller/plans/server.yaml.j2

@@ -1,4 +1,3 @@
-#% if bootstrap_distribution in ['k3s'] and addon_system_upgrade_controller.enabled %#
 ---
 apiVersion: upgrade.cattle.io/v1
 kind: Plan
@@ -22,4 +21,3 @@ spec:
     - {key: CriticalAddonsOnly, operator: Exists}
   upgrade:
     image: rancher/k3s-upgrade
-#% endif %#