fixed Python 3 keys() usage (#1861)

* fixed python3 keys()

* added changelog fragment

* Update plugins/modules/cloud/spotinst/spotinst_aws_elastigroup.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/cache/redis.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* rolledback redis.py per PR

* Update plugins/modules/monitoring/sensu/sensu_check.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* removed unnecessary ignore lines

* adding memcached and one case in redis is indeed necessary

* Update changelogs/fragments/1861-python3-keys.yml

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update changelogs/fragments/1861-python3-keys.yml

* Update changelogs/fragments/1861-python3-keys.yml

Co-authored-by: Felix Fontein <felix@fontein.de>

Co-authored-by: Felix Fontein <felix@fontein.de>

plugins/modules/cloud/oracle/oci_vcn.py

@@ -128,7 +128,7 @@ def update_vcn(virtual_network_client, module):
         primitive_params_update=["vcn_id"],
         kwargs_non_primitive_update={UpdateVcnDetails: "update_vcn_details"},
         module=module,
-        update_attributes=UpdateVcnDetails().attribute_map.keys(),
+        update_attributes=list(UpdateVcnDetails().attribute_map.keys()),
     )
     return result