Update stream_filter_ signature #4125
   Merged  
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Closes phpstan/phpstan#12380
Cf https://github.com/php/php-src/blob/f5aa69a5fc760463af8ffdd474119fc27eee83c1/ext/standard/basic_functions.stub.php#L3423
I think it can be anything (ie mixed) because people might write custom filter working with any shape of params.