Use of `FetchContent` with default policy settings has a warning starting with CMake 3.24. This opts those plugins into new behaviors for everything up through 3.24 to avoid those warnings.

The `VERSION` is used rather than an explicity policy setting since this is the approach recommended by CMake docs. For any policies that we aren't currently hitting, we would want new behavior by default in the future so that we don't accidentally depend on deprecated behavior.

See https://github.com/flutter/flutter/issues/116866