Fixed Cache\Backend\Redis::save

[sergeyklay]

• Type: bug fix
• Link to issue: Non-expiring cache keys  #12327

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Fixed Phalcon\Cache\Backend\Redis::save to allow save data termlessly:

// Set expiration to 10 second
$cache->save("my-key", $data, 10);

// Save data termlessly
$cache->save("my-key", $data, -1);

// Save data termlessly
$cache->save("my-key", $data, -1789789789);

// Save data termlessly
$cache->save("my-key", $data, 0);