Fix according to breaking changes in `ark-ec`

[autquis]

• Fixes due to arkworks-rs/algebra#746
• Removing the extra loop mentioned in #139

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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]

Thank you!

[Pratyush]

Lovely, thanks!