Add 'flush ip6tables' task in reset role (kubernetes-sigs#9168)

* Add 'flush ip6tables' task in reset role 

If enable_dual_stack_networks is set to true and ip6 is defined，ip6tables will be created. But when reset the kubernetes cluster, kubespray doesn't flush ip6tables.

* [CI] fix molecule tests on opensuse by upgrading to 15.4 (kubernetes-sigs#9175)

* [CI] fix molecule tests on opensuse by upgrading to 15.4

* [opensuse] use correct python crytography package name depending on distribution version

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

roles/reset/tasks/main.yml

@@ -205,6 +205,20 @@
   tags:
     - iptables
 
+- name: flush ip6tables
+  iptables:
+    table: "{{ item }}"
+    flush: yes
+    ip_version: ipv6
+  with_items:
+    - filter
+    - nat
+    - mangle
+    - raw
+  when: flush_iptables|bool and enable_dual_stack_networks
+  tags:
+    - ip6tables
+
 - name: Clear IPVS virtual server table
   command: "ipvsadm -C"
   ignore_errors: true  # noqa ignore-errors