update solr to latest Dockerfile

solr/README.md

@@ -1,6 +1,6 @@
 # Supported tags and respective `Dockerfile` links
 
--	[`5.3.1`, `5.3`, `5`, `latest` (*5.3/Dockerfile*)](https://github.com/docker-solr/docker-solr/blob/d716be08247ec27461d1d22c21d9909edfa46bbd/5.3/Dockerfile)
+-	[`5.3.1`, `5.3`, `5`, `latest` (*5.3/Dockerfile*)](https://github.com/docker-solr/docker-solr/blob/d722c55dd320a812e278a23c60a5d5616515df0b/5.3/Dockerfile)
 
 For more information about this image and its history, please see [the relevant manifest file (`library/solr`)](https://github.com/docker-library/official-images/blob/master/library/solr). This image is updated via pull requests to [the `docker-solr/docker-solr` GitHub repo](https://github.com/docker-solr/docker-solr).