test failure on 32 bit architectures

[davide125]

One test fails when building on i686 or armv7hl

---- src/lib.rs - (line 26) stdout ----
Test executable failed (exit code 101).
stderr:
thread 'main' panicked at 'assertion failed: `(left == right)`
  left: `12`,
 right: `8`', src/lib.rs:10:1
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failures:
    src/lib.rs - (line 26)

You can see the full logs at https://koji.fedoraproject.org/koji/taskinfo?taskID=70819940 and https://koji.fedoraproject.org/koji/taskinfo?taskID=70819939 (look at build.log).

[CAD97]

That's this doc test:

https://github.com/maciejhirsz/beef/blob/175938aeeb2bf82f365ab9852f514c9d29d7adba/src/lib.rs#L26-L34

The third assert is incorrect on 32 bit targets, since 32 bit targets reexport the 3-usize Cow (#40).

This is nonfatal, but should definitely still be fixed.