Instance flexibility in regional managed instance groups (MIGs) support the ANY target distribution shape

## Feature Feature Instance flexibility in regional managed instance groups (MIGs) support the `ANY` target distribution shape. Selecting this shape lets you maximize resource obtainability and the utilization of unused zonal reservations. For more information, see[About instance flexibility in MIGs](https://cloud.google.com/compute/docs/instance-groups/about-instance-flexibility).