Groups feedback: allow for multiple actors in feature flags

[joesaunderson]

Is your feature request related to a problem?

In our use case for groups, we want to target them in feature flags.

We want to be able to do this alongside person properties, for example.

All users who have the role X OR are part of group Y - currently, you can only target one 'actor' per feature flag.

Describe the solution you'd like

The ability to target multiple actors in the same feature flag criteria.

Describe alternatives you've considered

Two feature flags, which would be messy in the code.

Additional context

CC @lharress (we discussed on a call earlier) and @macobo for my ongoing groups feedback.

Thank you for your feature request – we love each and every one!