The definition files do not need to be executable anymore.
The definition files do not need to be executable anymore.

Update the CONTRIBUTING.md file accordingly.

hnw/php-build,rogeriopradoj/php-build,hirak/php-build,gerardroche/php-build,stof/php-build,php-build/php-build,circleci/php-build,michael-berlin/php-build,stof/php-build,0livier/php-build