Fix typo in redis URL scheme

There should only be two "s"es, not three, see
https://www.iana.org/assignments/uri-schemes/prov/redis

changelogs/unreleased/fix-typo-in-url-scheme.yml

+---
+title: Fix typo in redis URL scheme
+merge_request: 631
+author:
+type: fixed

internal/redis/redis.go

@@ -100,7 +100,7 @@ func sentinelConn(master string, urls []config.TomlURL) *sentinel.Sentinel {
 				redis.DialWriteTimeout(timeout),
 			}
 
-			if url.Scheme == "redis" || url.Scheme == "redisss" {
+			if url.Scheme == "redis" || url.Scheme == "rediss" {
 				c, err = redis.DialURL(addr, options...)
 			} else {
 				c, err = redis.Dial("tcp", url.Host, options...)