Ensure we are using the purpose build ES image in testing

Similar to elastic#17627

Author: donoghuc

x-pack/distributions/internal/observabilitySRE/qa/acceptance/docker/docker-compose.yml

@@ -14,7 +14,7 @@ services:
       - elasticsearch
 
   elasticsearch:
-    image: docker.elastic.co/elasticsearch/elasticsearch-fips:${ELASTICSEARCH_IMAGE_VERSION:-8.19.0-SNAPSHOT}
+    image: docker.elastic.co/cloud-release/elasticsearch-cloud-ess-fips:${ELASTICSEARCH_IMAGE_VERSION:-8.19.0-SNAPSHOT}
     container_name: fips_test_elasticsearch
     ports:
       - "9200:9200"
@@ -31,7 +31,7 @@ services:
   filebeat:
     # The filebeat shipped with the elasticsearch-fips container is built for FIPS support
     # There is no stand alone distribution. This uses the shipped version for testing. 
-    image: docker.elastic.co/elasticsearch/elasticsearch-fips:${FILEBEAT_IMAGE_VERSION:-8.19.0-SNAPSHOT}
+    image: docker.elastic.co/cloud-release/elasticsearch-cloud-ess-fips:${FILEBEAT_IMAGE_VERSION:-8.19.0-SNAPSHOT}
     container_name: fips_test_filebeat
     working_dir: /usr/share/filebeat
     entrypoint: ["/bin/bash", "-c"]