…v80)

This PR was merged into the 4.4 branch.

Discussion
----------

[Cache] Fix connecting to Redis via a socket file

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | #45277
| License       | MIT
| Doc PR        |

In the [commit](99b4885) was done follow changes in Traits/RedisTrait.php(188)

Old code:

```$port = $hosts[0]['port'] ?? null;```

New code:

```$port = $hosts[0]['port'] ?? 6379;```

With DSN "redis:///var/run/redis/redis.sock" raise an error:

```
Redis connection "redis:///var/run/redis/redis.sock?dbindex=5" failed: php_network_getaddresses: getaddrinfo failed: Name or service not known
```

Because phpredis doesn't allow socket connections with a port

```
(new Redis)->connect('/var/run/redis/redis.sock', 6379);
```

**Error**

```
PHP Warning:  Redis::connect(): php_network_getaddresses: getaddrinfo failed: Name or service not known in /root/test_redis.php on line 5
PHP Fatal error:  Uncaught RedisException: php_network_getaddresses: getaddrinfo failed: Name or service not known in /root/test_redis.php:5
Stack trace:
#0 /root/test_redis.php(5): Redis->connect()
#1 {main}
  thrown in /root/test_redis.php on line 5
```

I added additional validation of connection type (by host or socket). Also I fixed condition when RedisSentinel connection call as it supports connections by host only.

Commits
-------

214fdd1 [Cache] Fix connecting to Redis via a socket file