Add Product Analytics Experiment toggle

What does this MR do and why?

We're adding product analytics to experiments list. Currently, there is a 'Experiment and beta features' checkbox in the group settings page. However, we would like to control product analytics independently of other experiments, as well. For this, product analytics will have its own toggle. This is important because we need a way to disable opt-in into the product analytics feature in case we cannot handle the amount of users already opted in.

Currently, the experiment features settings is only allowed if ai features are enabled. This MR removes this condition, as experiments and beta features is not AI specific and now we're introducing product analytics.

Note: product analytics features should depend on experiment features, i.e. product analytics enabled but experiments disabled is an invalid scenario.

Note: This MR only adds the migration and the checkbox. The code checking this new field in the Dashboards graphql resolver will be added in a follow-up MR to prevent MR being too large. That's why documentation change is also not included in this MR.

Screenshots or screen recordings

How to set up and validate locally

1. Run gdk in SAAS mode
2. Visit a group edit page -> Permissions and group features
3. You should see the new checkbox "Use product analytics"
4. You should be able to change its value to false anytime.
5. You should be able to change its value to true only if "Experiment and Beta features" is enabled.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #414865 (closed)