Add option to exclude experiments in targeting

[jaredlockhart]

Let's add a multi select drop down in the Audience page that says

Exclude Experiments

and lists all draft/preview/live experiments (except the one being edited)

and then when we generate the targeting strings we can say something like

!("selected-exclude-experiment-slug" in activeExperiments") && !("other-exclude-experiment-slug" in activeExperiments) && ....

We'll need to check with @jhugman to know what the actual variables that store active experiments are for mobile.

On desktop it's

https://github.com/mozilla/experimenter/blob/main/app/experimenter/experiments/models.py#L359

This will let us automate experiment exclusion targeting without needing custom advanced targeting configs.

┆Issue is synchronized with this Jira Task

[data-sync-user]

➤ James Hugman commented:

This isn’t quite implemented yet.

https://mozilla-hub.atlassian.net/browse/EXP-2545 ( https://mozilla-hub.atlassian.net/browse/EXP-2545|smart-link ) is done, but this is awaiting https://mozilla-hub.atlassian.net/browse/EXP-2735 ( https://mozilla-hub.atlassian.net/browse/EXP-2735|smart-link ).

Once this is implemented, the given JEXL expression is:

active_experiments[“selected-exclude-experiment-slug”] != null && active_experiments[“other-exclude-experiment-slug”] != null &&