mozjpeg DecompressScanlines::read_scanlines is Unsound

This issue and vector is similar to RUSTSEC-2020-0029 of rgb crate which mozjpeg depends on.

Affected versions of mozjpeg crate allow creating instances of any type T from bytes, and do not correctly constrain T to the types for which it is safe to do so.

Examples of safety violation possible for a type T:

• T contains a reference type, and it constructs a pointer to an invalid, arbitrary memory address.
• T requires a safety and/or validity invariant for its construction that may be violated.

The issue was fixed in 0.8.19 by using safer types and involving rgb dependency bump.