Fix ios test pt. 2 (#40628)

* Add missing idempotence assert

* Remove dhcp with other addresses on ipv6

test/integration/targets/ios_l3_interface/tests/cli/basic.yaml

@@ -168,6 +168,8 @@
     provider: "{{ cli }}"
   register: result
 
+- assert: *unchanged
+
 - name: Delete second interface ipv4 and ipv6 address (setup)
   ios_l3_interface:
     name: "{{ test_interface2 }}"