Remove yarn

[Kevin101Zhang]

We previously managed our packages with two different package managers, which often led to confusion and inconsistencies within the repository. Some parts of the codebase used Yarn, while others, like Docker configurations, relied on npm.

This setup resulted in numerous dependency mismatches/conflucts, duplicate caching and storage, and larger build times. To align with the majority of our repository, which already uses npm (e.g., our runner scripts), I remove Yarn entirely and standardize on npm. I eliminated all references to Yarn, including removing the yarn.lock file/cache. Additionally, we updated our Dockerfile from using Node.js version 16 to version 18 to meet the requirements of our applications and removed the reference to yarn in our dockerfile. Which is odd because our local dockerfile used yarn while our dockerfile on gcp references npm?