Fixes an fqdn error (ansible#31745)

the pool module was not correctly interpreting the partitions
in the monitors list vs the partition at the task level. This patch
fixes that.

lib/ansible/modules/network/f5/bigip_pool.py

@@ -110,7 +110,7 @@
     default: Common
     version_added: 2.5
 notes:
-  - Requires BIG-IP software version >= 11.
+  - Requires BIG-IP software version >= 12.
   - F5 developed module 'F5-SDK' required (https://github.com/F5Networks/f5-common-python).
   - Best run as a local_action in your playbook.
 requirements:
@@ -399,12 +399,9 @@ def lb_method(self):
         return lb_method
 
     def _fqdn_name(self, value):
-        if value.startswith('/'):
-            name = os.path.basename(value)
-            result = '/{0}/{1}'.format(self.partition, name)
-        else:
-            result = '/{0}/{1}'.format(self.partition, value)
-        return result
+        if value is not None and not value.startswith('/'):
+            return '/{0}/{1}'.format(self.partition, value)
+        return value
 
     @property
     def monitors_list(self):