Update README.md

Added more information for the GITHUB_ACTION as it was confusing and no details were provided.

README.md

@@ -40,7 +40,7 @@ jobs:
       - name: AI Code Reviewer
         uses: your-username/ai-code-reviewer@main
         with:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} # The GITHUB_TOKEN is there by default so you just need to keep it like it is and not necessarily need to add it as secret as it will throw an error. [More Details](https://docs.github.com/en/actions/security-guides/automatic-token-authentication#about-the-github_token-secret)
           OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
           OPENAI_API_MODEL: "gpt-4" # Optional: defaults to "gpt-4"
           exclude: "**/*.json, **/*.md" # Optional: exclude patterns separated by commas