Background:
Today we use --headless if there's no DISPLAY that has been exported. By adding a configuration you can more easily turn on/off headless, making it possible to test with or without use browser built in headless (running headless is recommended by webdriverIO).
This is similar to T410594: Add configuration to enable/disable video recording for webdriverio tests.
Acceptance Criteria:
- Add a configuration in wdio-defaults.conf.js for core where you can set the headless behavior, but keep default functionality.
- the configuration should be changed in wdio.conf.js