Release 2.16.6: Support Elasticsearch 7.14+ (#2238)

# Why this need some changes by our side?

There is a new feature introduced in 7.14 version of Elasticsearch and enabled by default. This one create an index called `.geoip_databases` incompatible with the custom Kuzzle data model.
It can be disabled in the `elasticsearch.yml`:
```yaml
ingest:
  geoip:
    downloader:
      enabled: false
```
But since this is enable by default, we need to ignore the automatically created index to avoid issues when using the native index:stats Elasticsearch API action

.ci/test-cluster.yml

@@ -78,7 +78,7 @@ services:
     container_name: kuzzle_redis
 
   elasticsearch:
-    image: kuzzleio/elasticsearch:7
+    image: kuzzleio/elasticsearch:7.16.2
     container_name: kuzzle_elasticsearch
     ulimits:
       nofile: 65536

lib/service/storage/elasticsearch.js

@@ -237,6 +237,12 @@ class ElasticSearch extends Service {
     let size = 0;
 
     for (const [indice, indiceInfo] of Object.entries(body.indices)) {
+      // Ignore non-Kuzzle indices
+      if ( indice[INDEX_PREFIX_POSITION_IN_INDICE] !== PRIVATE_PREFIX
+        && indice[INDEX_PREFIX_POSITION_IN_INDICE] !== PUBLIC_PREFIX ) {
+        continue;
+      }
+
       const alias = await this._getAliasFromIndice(indice);
       const indexName = this._extractIndex(alias);
       const collectionName = this._extractCollection(alias);

package.json

@@ -1,7 +1,7 @@
 {
   "name": "kuzzle",
   "author": "The Kuzzle Team <[email protected]>",
-  "version": "2.16.5",
+  "version": "2.16.6",
   "description": "Kuzzle is an open-source solution that handles all the data management through a secured API, with a large choice of protocols.",
   "bin": {
     "kuzzle": "bin/start-kuzzle-server"

test/service/storage/elasticsearch.test.js

@@ -111,7 +111,11 @@ describe('Test: ElasticSearch service', () => {
             },
             '&test-index.test-collection': {
               total: { docs: { count: 2 }, store: { size_in_bytes: 20 } }
-            }
+            },
+            '.kibana': {
+              total: { docs: { count: 2 }, store: { size_in_bytes: 42 } }
+            },
+            '.geoip_databases': { /* This index nativement do not return anything on index:stats call */ }
           }
         }
       });