change call_user_func* with self invoked function

[weierophinney]

• Is this related to quality assurance?
  As we already require php ^7.1 in develop branch

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Originally posted by @samsonasik at zendframework/zend-servicemanager#265

[weierophinney]

Scheduling for 4.0, as we support PHP 5.6 still in the 3.X series.

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Originally posted by @weierophinney at zendframework/zend-servicemanager#265 (comment)

[samsonasik]

closed in favor of #37