Fix: set fallback value of kubelet ip6 (#8858) (#8926)

* Fix: set fallback value of kubelet ip6 (#8858)

* Prune the spurious comma in the end of kubelet_address

- Update `roles/kubernetes/node/defaults/main.yml`

Co-authored-by: Cristian Calin <6627509+cristicalin@users.noreply.github.com>

* Fix: set fallback value of kubelet ip6 (#8858)

- Apply the lint: 132606368e

Co-authored-by: Cristian Calin <6627509+cristicalin@users.noreply.github.com>

roles/kubernetes/node/defaults/main.yml

@@ -3,7 +3,7 @@
 kube_apiserver_insecure_bind_address: 127.0.0.1
 
 # advertised host IP for kubelet. This affects network plugin config. Take caution
-kubelet_address: "{{ ip | default(fallback_ips[inventory_hostname]) }}{{ ',' + ip6 if enable_dual_stack_networks and ip6 is defined }}"
+kubelet_address: "{{ ip | default(fallback_ips[inventory_hostname]) }}{{ (',' + ip6) if enable_dual_stack_networks and ip6 is defined else '' }}"
 
 # bind address for kubelet. Set to 0.0.0.0 to listen on all interfaces
 kubelet_bind_address: "{{ ip | default('0.0.0.0') }}"