Keep publishing Docker labels in specific Docker Hub context (elastic#126989) (elastic#127305)

These labels are incompatible with the Docker Hub, but for now we need
to keep them to override the labels coming from the base image.

Author: jozala

distribution/docker/build.gradle

@@ -575,7 +575,7 @@ for (final Architecture architecture : Architecture.values()) {
     }
     if(base == DockerBase.DEFAULT) {
       // Add additional docker hub specific context which we use solely for publishing to docker hub.
-      // At the moment it only differs in not labels added that we need for openshift certification
+      // At the moment it is exactly the same as the default context.
       addBuildDockerContextTask(architecture, base, 'DockerHubContext', "docker-hub-build-context")
     }
   }

distribution/docker/src/docker/Dockerfile.default

@@ -139,15 +139,13 @@ LABEL org.label-schema.build-date="${build_date}" \\
   org.opencontainers.image.vendor="Elastic" \\
   org.opencontainers.image.version="${version}"
 
-<% if (docker_context != 'docker-hub-build-context') { %>
 LABEL name="Elasticsearch" \\
   maintainer="[email protected]" \\
   vendor="Elastic" \\
   version="${version}" \\
   release="1" \\
   summary="Elasticsearch" \\
   description="You know, for search."
-<% } %>
 
 RUN mkdir /licenses && ln LICENSE.txt /licenses/LICENSE