Fix README.md File read error

[yashksaini-coder]

This PR addresses an issue with the automated README update process and improves the robustness of our scripts. The main changes are:

1. Modified scripts/index.js:

   • Added imports for path and fileURLToPath to handle file paths correctly.
   • Implemented a more robust method to locate the README.md file using __dirname and path.join().
   • Updated file reading and writing operations to use the correct file path.

2. Updated .github/workflows/readme.yml:

   • Adjusted the workflow to ensure it runs in the correct directory when executing the script.
   • Added a working-directory parameter to relevant steps to ensure consistency.

3. README.md:

   • No direct changes to the content, but the script can now reliably locate and update this file.

These changes resolve a "file not found" error that was preventing the automatic update of the README with the Leetcode solutions table. The script is now more resilient to different execution environments and directory structures.