Allow for some if not all Custom Scripting to apply alongside experiments

[scottjehl]

Currently, experiment scripts run in place of any scripting that's applied to a test. Many scripting features should be compatible with experiments, while some (like multistep tests) may not.

We should aim to preserve scripting in experiments.

[kevinfarrugia]

This ticket was closed but scripts are still not being copied onto experiments.

Example: https://www.webpagetest.org/video/compare.php?tests=220801_AiDcWC_539,220801_AiDc2D_537

navigate %url%/learn

[scottjehl]

Thanks @kevinfarrugia

This was partly addressed but you're right that it's not fully fixed yet. We intend to keep what we can of scripts, but some settings will have to be overridden for the experiment itself (which also uses scripting).

[github-actions]

We're in the process of cleaning up issues on this project in order to ensure we're able to stay on top of high priority bugs and feature requests. As a part of this process, we're automatically closing any issues that have had no activity within the last two years, including this one, since the codebase has changed dramatically in that time. If you feel this is still relevant, please file a new issue using the relevant issue template so we can get it prioritized. Thanks!