Remove _all configuration

Since the `_all` field is now disabled by default and no longer allowed to be
configured, these should be removed from the mapping templates.

Relates to https://github.com/elastic/elasticsearch/pull/22144

Original commit: elastic/x-pack-elasticsearch@3b17c2b9c6

elasticsearch/src/main/resources/monitoring-es.json

@@ -8,9 +8,6 @@
   },
   "mappings": {
     "_default_": {
-      "_all": {
-        "enabled": false
-      },
       "date_detection": false,
       "properties": {
         "cluster_uuid": {

elasticsearch/src/main/resources/monitoring-kibana.json

@@ -7,9 +7,6 @@
   },
   "mappings": {
     "_default_": {
-      "_all": {
-        "enabled": false
-      },
       "properties": {
         "cluster_uuid": {
           "type": "keyword"

elasticsearch/src/main/resources/monitoring-logstash.json

@@ -7,9 +7,6 @@
   },
   "mappings": {
     "_default_": {
-      "_all": {
-        "enabled": false
-      },
       "properties": {
         "cluster_uuid": {
           "type": "keyword"

elasticsearch/src/main/resources/security_audit_log.json

@@ -7,9 +7,6 @@
   "mappings": {
     "event": {
       "dynamic" : "strict",
-      "_all" : {
-        "enabled" : false
-      },
       "properties": {
         "@timestamp": {
           "type": "date",

elasticsearch/src/main/resources/triggered_watches.json

@@ -10,9 +10,6 @@
   "mappings": {
     "triggered_watch": {
       "dynamic" : "strict",
-      "_all" : {
-        "enabled" : false
-      },
       "properties": {
         "trigger_event": {
           "type": "object",

elasticsearch/src/main/resources/watch_history.json

@@ -40,9 +40,6 @@
         }
       ],
       "dynamic": false,
-      "_all": {
-        "enabled": false
-      },
       "properties": {
         "watch_id": {
           "type": "keyword"

elasticsearch/src/main/resources/watches.json

@@ -9,9 +9,6 @@
   "mappings": {
     "watch": {
       "dynamic" : "strict",
-      "_all" : {
-        "enabled" : false
-      },
       "properties": {
         "_status": {
           "type": "object",

elasticsearch/src/test/java/org/elasticsearch/xpack/monitoring/exporter/local/LocalExporterTemplateTests.java

@@ -185,9 +185,6 @@ public class LocalExporterTemplateTests extends MonitoringIntegTestCase {
                                 .endObject()
                                 .startObject("mappings")
                                     .startObject("_default_")
-                                        .startObject("_all")
-                                            .field("enabled", false)
-                                        .endObject()
                                         .field("date_detection", false)
                                         .startObject("properties")
                                             .startObject("cluster_uuid")