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/ks.yaml.j2

@@ -1,4 +1,3 @@
-#% if bootstrap_distribution in ['k3s'] and addon_system_upgrade_controller.enabled %#
 ---
 apiVersion: kustomize.toolkit.fluxcd.io/v1
 kind: Kustomization
@@ -41,4 +40,3 @@ spec:
   interval: 30m
   retryInterval: 1m
   timeout: 5m
-#% endif %#