Adding TROUBLESHOOTING section for CONTAINERS.md
Adding TROUBLESHOOTING section for CONTAINERS.md

In the [Hyrax Slack channel][1], I posted a problem regarding a bad
address in solr.  In discussion we settled on trying `docker-compose down
--volumes`. That worked.

[1]:https://samvera.slack.com/archives/CA8ANGLEL/p1619093684012400

samvera/hyrax,samvera/hyrax,samvera/hyrax,samvera/hyrax