Switch to using RPITIT for to_base_prime_field_elements

[Pratyush]

Description

---

Before we can merge this PR, please make sure that all the following items have been
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• Targeted PR against correct branch (master)
• 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

[mmagician]

We're still at minimum supported rust-version = "1.70", so we'd need to bump to 1.75 first, which would be pretty limiting to some projects.

[Pratyush]

We can hold off on this for a couple of release, just wanted to get this on the radar.

[Pratyush]

It's been a few releases, so maybe we can merge this now?

[mmagician]

@Pratyush sounds good, could you also bump the minimum rust-version together with this PR?

[Pratyush]

Done!