Update examples from "ruby:2.5" to "ruby:3.0"
Update examples from "ruby:2.5" to "ruby:3.0"

nats-io/docker-docs,jetty-project/docker-docs,Bonitasoft-Community/docker_docs,crate/docker-docs,Lightstreamer/docs,nats-io/docker-docs,jetty-project/docker-docs,Bonitasoft-Community/docker_docs,docker-solr/docs,infosiftr/docker-library-docs,Lightstreamer/docs,infosiftr/docker-library-docs,docker-library/docs,docker-solr/docs,crate/docker-docs,docker-library/docs