I understand what you asked for. You wanted to know what was the guice version used? But as was said in the other thread Version of org.elasticsearch.common.inject library used in Elasticsearch 7.10.2, you should upgrade your version...
But anyway, the java code is now living in elasticsearch/server/src/main/java/org/elasticsearch/common/inject at main · elastic/elasticsearch · GitHub and I'm not sure there's a direct dependency to Guice anymore.