Affected: crates.io: arrow2

The struct `Ffi_ArrowArray` implements `#derive(Clone)` that is inconsistent with its custom implementation of `Drop`, resulting in a double free when cloned.

Cloning this struct in `safe` results in a segmentation fault, which is unsound.

This derive was removed from this struct. All users are advised to either: * bump the patch version of this crate (for versions `v0.7,v0.8,v0.9`), or * migrate to a more recent version of the crate (when using `<0.7`).

Doing so elimitates this vulnerability (code no longer compiles).