fix(cache): Set default Redis port to 0 for UNIX sockets

When using phpredis with a UNIX socket, the port should either not be specified at all or be `<1`. 

https://github.com/phpredis/phpredis?tab=readme-ov-file#connect-open

https://github.com/phpredis/phpredis/blob/d0b0c5cfdde9d49a265ca4bf7184e3998863aed0/library.c#L3332-L3334

Fixes #54813

Signed-off-by: Josh <josh.t.richards@gmail.com>

Author: joshtrichards

lib/private/RedisFactory.php

@@ -77,7 +77,7 @@ private function create() {
 			$this->instance = new \Redis();
 
 			$host = $config['host'] ?? '127.0.0.1';
-			$port = $config['port'] ?? ($host[0] !== '/' ? 6379 : null);
+			$port = $config['port'] ?? ($host[0] !== '/' ? 6379 : 0);
 
 			$this->eventLogger->start('connect:redis', 'Connect to redis and send AUTH, SELECT');
 			// Support for older phpredis versions not supporting connectionParameters