Fix use of wrong fields in Cisco ASA dashboard (elastic#15553)

This dashboard wasn't updated after a couple of fields were renamed.

Fixes: elastic#15420

CHANGELOG.next.asciidoc

@@ -234,6 +234,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - netflow: Allow for options templates without scope fields. {pull}15449[15449]
 - netflow: Fix bytes/packets counters on some devices (NSEL and Netstream). {pull}15449[15449]
 - netflow: Fix compatibility with some Cisco devices by changing the field `class_id` from short to long. {pull}15449[15449]
+- Fixed dashboard for Cisco ASA Firewall. {issue}15420[15420] {pull}15553[15553]
 
 *Heartbeat*
 

x-pack/filebeat/module/cisco/_meta/kibana/7/dashboard/Filebeat-Cisco-ASA.json

@@ -764,7 +764,7 @@
               "id": "2",
               "params": {
                 "customLabel": "ACL ID",
-                "field": "cisco.asa.list_id",
+                "field": "cisco.asa.rule_name",
                 "missingBucket": false,
                 "missingBucketLabel": "Missing",
                 "order": "desc",
@@ -878,7 +878,7 @@
               "params": {
                 "aggregate": "concat",
                 "customLabel": "Sample message",
-                "field": "log.original",
+                "field": "event.original",
                 "size": 1,
                 "sortField": "@timestamp",
                 "sortOrder": "desc"