feat(nimbus): Add subscribers field to feature config model.

[b4handjr]

Because

• We want to allow a user to subscribe to a feature and get notifications when that feature is used

This commit

• Adds the subscribers field to the Feature Config class.

Fixes #13783

[yashikakhurana]

ahaa I see adding a subscriber for that, just a suggestion the name subscriber is little bit confusing for me, as we have subscriber for the experiments too, seeing the same field might be little confusing 🤔

[freshstrangemusic]

ahaa I see adding a subscriber for that, just a suggestion the name subscriber is little bit confusing for me, as we have subscriber for the experiments too, seeing the same field might be little confusing 🤔

Its the same name on two different models. And the concept is the same -- a subscription.

We have types, I don't see this being a problem.

[freshstrangemusic]

This needs a ruff format.

[b4handjr]

We must have a bug on our make lint step as it sometimes doesn't report these.

[yashikakhurana]

yeah I understand the concept is same, I said it is confusing for me :D, lets