[redis] Update metric names to conform to #5837

receiver/redisreceiver/README.md

@@ -26,15 +26,15 @@ The Redis receiver turns this data into a gauge...
 func usedCPUSys() *redisMetric {
 	return &redisMetric{
 		key:    "used_cpu_sys",
-		name:   "redis/cpu/time",
+		name:   "redis.cpu.time",
 		units:  "s",
 		mdType: metricspb.MetricDescriptor_GAUGE_DOUBLE,
 		labels: map[string]string{"state": "sys"},
 	}
 }
 ```
 
-with a metric name of `redis/cpu/time` and a units value of `s` (seconds).
+with a metric name of `redis.cpu.time` and a units value of `s` (seconds).
 
 ## Configuration