Tweak version detection in setup-integration-tests script

[jbrada]

I've made some changes to the setup-integration-test script that addresses an issue where it was not possible to use the script when a specific configuration of Xdebug was in place.

With this pull request, I've tweaked the version detection to evaluate only rows with the Magento string. The tweak should help to resolve the issue and make the script more reliable overall.

(this is an example output of bin/magento --version --no-ansi when xdebug is enabled on each request and disabled PHPStorm's Listening for Debug Connection)

Thank you @markshust for your hard work in maintaining this package!

[what-the-diff]

PR Summary

• Updated script to support Magento 2.3
  The script has been improved to work with the latest version of Magento (2.3).
• Switched to using grep for parsing version number
  The method to extract the version number has been changed from cut to grep, providing better reliability in parsing the version information from bin/magento --version output.

[piotrkwiecinski]

Looks good