Small cleanup, removed duplicated keys from array

[hostep]

trafficstars

'proc_open' => null, is already defined in the same array on line 38, it makes no sense to keep both around.

Found with phpstan (while running it from inside magento core codebase):

$ ./vendor/bin/phpstan analyse --level=0 -c dev/tests/static/testsuite/Magento/Test/Php/_files/phpstan/phpstan.neon vendor/magento | grep 'duplicate'
 3325/3325 [▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓] 100%

  28     Array has 2 duplicate keys with value 'proc_open' ('proc_open', 'proc_open').