Change pull request trigger in order to get permissions back in order

[igorpecovnik]

Description

Changing trigger to pull_request_target which should deal with permission properly.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules