fix: update node version

[dristpunk]

Closes BES-120
Closes BES-130

[linear]

BES-120 Update node to version 18

All actions should use node 18+. It will probably take a while to update every action in every project and fix possible issues that arise from the upgrade but we have time till February 2024.

Context:

#47

https://github.com/defi-wonderland/solidity-foundry-boilerplate/actions/runs/6865845134/job/18670757578?pr=32

The announcement:

On August 15th 2023, Node.js 14 will be disabled in the Project Settings and existing Projects that have Node.js 14 selected will render an error whenever a new Deployment is created. The same error will show if the Node.js version was configured in the source code.

On February 6th 2024, Node.js 16 will be disabled in the Project Settings and existing Projects that have Node.js 16 selected will render an error whenever a new Deployment is created. The same error will show if the Node.js version was configured in the source code.

While existing Deployments with Serverless Functions will not be affected, Vercel strongly encourages upgrading to Node.js 18 to ensure you receive security updates (using either engines in package.json or the General page in the Project Settings).

[linear]

BES-130 Update README in Solidity exporter