RUSTSEC-2020-0136: CopyCell lacks bounds on its Send trait allowing for data races

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CopyCell lacks bounds on its Send trait allowing for data races

Details
Package	toolshed
Version	0.6.3
URL	ratel-rust/toolshed#12
Date	2020-11-15

CopyCell<T> is a Cell-like type that is implemented for any type T that
is Copyable. It's Send trait has no bounds on the contained type.

As not all Copyable types are thread safe, for example non-mutable references
implement the Copy trait, it is possible to send references to types with
interior mutability such as Cell across threads and cause data races.

See advisory page for additional details.