ce_snmp_target_host: update to fix bug: None has no 'lower()' function. (#57904)

* update to fix bug: None has not 'lower()' function.

* add a changelog fragment.

* update changlog fragment.

* Update 57904-ce_snmp_target_host.yml

changelogs/fragments/57904-ce_snmp_target_host.yml

@@ -0,0 +1,3 @@
+---
+bugfixes:
+  - ce_snmp_target_host - None has no 'lower()' attribute.

lib/ansible/modules/network/cloudengine/ce_snmp_target_host.py

@@ -493,8 +493,11 @@ class SnmpTargetHost(object):
                                 same_flag = False
 
                         if "interface-name" in tmp.keys():
+                            if tmp.get("interface-name") is not None:
                                 if tmp["interface-name"].lower() != self.interface_name.lower():
                                     same_flag = False
+                            else:
+                                same_flag = False
 
                         if same_flag:
                             break