Implement getDatabaseName() in CockroachContainer (#3778)

Co-authored-by: Sergei Egorov <bsideup@gmail.com>

Author: croemmich

modules/cockroachdb/src/main/java/org/testcontainers/containers/CockroachContainer.java

@@ -68,6 +68,11 @@ public String getJdbcUrl() {
             "/" + databaseName + additionalUrlParams;
     }
 
+    @Override
+    public final String getDatabaseName() {
+        return databaseName;
+    }
+
     @Override
     public String getUsername() {
         return username;