chore: use expect(..) instead of assert(..)

[fredbonin]

Issue #240

Description of changes

Used expect instead of assert for all unit tests

Checklist

• [N/A] Created unit tests in tests/unit and/or in Rust for my feature if needed
• [X] Ran make fix to format JS and apply Clippy auto fixes
• [X] Made sure my code didn't add any additional warnings: make check
• [N/A] Updated documentation if needed (API.md/README.md/Other)

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[fredbonin]

Fantastic! Can we now remove deps on assert and update docs? Readme references assert module

Definitely, but with all the changes I think it would be better to do it in a second PR. What do you think ?