Updated depreciated code.

[tkreindler]

Updated a bunch of depreciated code to its modern equivalent.

Notable changes:

• 0...8 => 0..=8
• mem::uninitialized() => mem::MaybeUninit::uninit().assume_init()

[ids1024]

As I understand it, calling .assume_init() on uninitialized memory is considered undefined behavior. The code needs a further rewrite to avoid this.

Edit: From the documentation:

It is up to the caller to guarantee that the MaybeUninit really is in an initialized state. Calling this when the content is not yet fully initialized causes immediate undefined behavior.

[rivy]

Thanks for the contribution!
The fix for this same issue was already included in a large lint and CICD fixup PR (#1449).
We'd be happy to see you back with new contributions in the future.