fix new clippy warnings

[tessico]

Description

fixes unnecessary cast.
This was not caught before since it's a new improvement in 1.66 clippy: https://github.com/rust-lang/rust-clippy/blob/master/CHANGELOG.md#rust-166

closes: #XXXX

---

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• Targeted PR against correct branch (main)
• Linked to GitHub issue with discussion and accepted design OR have an explanation in the PR that describes this work.
• Wrote unit tests
• Updated relevant documentation in the code
• Added a relevant changelog entry to the Pending section in CHANGELOG.md
• Re-reviewed Files changed in the GitHub PR explorer

[alxiong]

can we just target this commit to #150 instead?

[tessico]

I wanted to keep it separate. I'm not sure how long the review process for #150 would take :)

[tessico]

If you strongly object to having it separate I don't mind that much.