docs: 👻 Include learning tool + Update deprecated tool

[yonathan9669]

Learning Tool

• SpeedRunEthereum A highly qualified walkthrough learning platform for Ethereum developers.

Template Tool | Update deprecated tool

• scaffold-eth-2 replaced the previous version.
• scaffold-eth is no longer maintained.
• Repo link updated.

Descriptions extracted from repos README.md

Checklist

• [x] The URL is not already present in the list (check with CTRL/CMD+F in the raw markdown file).
• [x] Each description starts with an uppercase character and ends with a period.
  Example: solc-js - JavaScript bindings for the compiler.
• [x] Drop all A / An prefixes at the start of the description.
• [x] Avoid using the word Solidity in the description.