Trait Mismatch Error When Building the Project with `cargo build`

I am currently working on a project and encountered a trait mismatch error in the x86_64 crate while building. Since I don't have time to rewrite the library, I decided to test the crate separately by cloning it and attempting to build it.

Steps I followed:

Cloned the repository and tried building it on a fresh setup.
Encountered the same error related to a trait mismatch in the steps_between method in the x86_64 crate.

The error message I am receiving is as follows:

error[E0053]: method `steps_between` has an incompatible type for trait
   --> /home/masterplan/.cargo/registry/src/index.crates.io-6f17d22bba15001f/x86_64-0.15.1/src/addr.rs:362:51
    |
362 |     fn steps_between(start: &Self, end: &Self) -> Option<usize> {
    |                                                   ^^^^^^^^^^^^^ expected `(usize, Option<usize>)`, found `Option<usize>`
    |
    = note: expected signature `fn(&addr::VirtAddr, &addr::VirtAddr) -> (usize, Option<usize>)`
               found signature `fn(&addr::VirtAddr, &addr::VirtAddr) -> Option<usize>`
help: change the output type to match the trait
    |
362 |     fn steps_between(start: &Self, end: &Self) -> (usize, Option<usize>) {
    |                                                   ~~~~~~~~~~~~~~~~~~~~~~

Steps to reproduce:

Clone the repository and enter the directory:

git clone https://github.com/rust-osdev/x86_64
cd x86-64

Set the Rust toolchain to nightly (already set in my environment):
```
rustup default nightly
```
Attempt to build the project with the following command:
```
cargo build
```

Result:
The build fails with the error related to the trait mismatch, as shown in the terminal output above.

Screenshots/Terminal Output:

rust-osdev / x86_64

Trait Mismatch Error When Building the Project with `cargo build` #512