Meraki module utility - get_net() downloads networks if data isn't provided (#41423)

* Enable get_net() to download nets if data isn't provided

- Currently, get_net() requires data to be passed to it
- PR enables get_net() to download all networks if data isn't passed
- Slightly simpler code
- Best practice is to download nets early in execution

* Apply fixes related to get_net()

* Removed extra code from the rebase

lib/ansible/modules/network/meraki/meraki_network.py

@@ -206,7 +206,7 @@ def main():
         elif meraki.params['net_name'] or meraki.params['net_id'] is not None:
             meraki.result['data'] = meraki.get_net(meraki.params['org_name'],
                                                    meraki.params['net_name'],
-                                                   nets
+                                                   data=nets
                                                    )
     elif meraki.params['state'] == 'present':
         if meraki.params['net_name']:  # FIXME: Idempotency check is ugly here, improve