Update docker.elastic.co/elasticsearch/elasticsearch Docker tag to v8.15.3 (#771)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.drone.yml

@@ -65,7 +65,7 @@ services:
   - name: redis
     image: redis:7.2.5
   - name: elastic
-    image: docker.elastic.co/elasticsearch/elasticsearch:8.14.3
+    image: docker.elastic.co/elasticsearch/elasticsearch:8.15.3
     environment:
       discovery.type: single-node
       xpack.security.enabled: false