treewide: silence mock structs unused warning

[wprzytula]

With a new version of Rust toolchain (stable 1.78.0), our never constructed structs used for testing macros began to trigger rustc warnings. Now, they are silenced explicitly using #[allow(unused)].

Pre-review checklist

• I have split my patch into logically separate commits.
• All commit messages clearly explain what they change and why.
• [ ] I added relevant tests for new features and bug fixes.
• All commits compile, pass static checks and pass test.
• PR description sums up the changes and reasons why they should be introduced.
• [ ] I have provided docstrings for the public items that I want to introduce.
• [ ] I have adjusted the documentation in ./docs/source/.
• [ ] I added appropriate Fixes: annotations to PR description.

[wprzytula]

If considerably many users are already using the new toolchain, we may want to consider releasing a patch version to silence those warnings.

[github-actions]

cargo semver-checks found no API-breaking changes in this PR! 🎉🥳
Checked commit: 3455abf

[Lorak-mmk]

If considerably many users are already using the new toolchain, we may want to consider releasing a patch version to silence those warnings.

I see only changes in tests, it should not affect users of the driver so I don't see the point at all.

When are the warnings fixed by this PR triggered? I didn't see any failed CI runs because of this.
Also, instead of saying new version of Rust toolchain please specify the version - someone reading this in the future won't know what version you had in mind without checking release dates.

[wprzytula]

I see only changes in tests, it should not affect users of the driver so I don't see the point at all.

Agreed.

When are the warnings fixed by this PR triggered? I didn't see any failed CI runs because of this.

They pop up when I run cargo check --all-targets.

Also, instead of saying new version of Rust toolchain please specify the version - someone reading this in the future won't know what version you had in mind without checking release dates.

Done.

[Lorak-mmk]

When are the warnings fixed by this PR triggered? I didn't see any failed CI runs because of this.

They pop up when I run cargo check --all-targets.

Then why is CI not failing on other PRs?

[Lorak-mmk]

Ah, it's probably not failing because we use Rust provided on CI runner images instead of setting up our own and I guess they were not updated yet.
We should probably change this at some point to use latest stable always.

[Lorak-mmk]

Eh, I forgot to check the commit message and you use new version of Rust toolchain there too.
Well, it's too late now and it's not that important