remove warning from jobacct_gather cgroup plugin since it is no longer

experimental

src/plugins/jobacct_gather/cgroup/jobacct_gather_cgroup.c

@@ -191,9 +191,6 @@ extern int init (void)
 			free_slurm_cgroup_conf(&slurm_cgroup_conf);
 			return SLURM_ERROR;
 		}
-		info("WARNING: The %s plugin is experimental, and should "
-		     "not currently be used in production environments.",
-		     plugin_name);
 	}
 
 	verbose("%s loaded", plugin_name);