Fix for new line race condition

[rudolfratusinski]

In high throughput environments writing message and PHP_EOL separately causes race condition issues, where messages might be written in order

• message
• message
• EOL
• EOL

instead of

• message
• EOL
• message
• EOL

An example below is a laravel application queue workers handled by supervisor.

Before:

After:

[symfony-bot]

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