Updated github MCP service config

[lokeshjain2008]

config for GitHub MCP was incorrect, I updated it to a working configuration.

Description

Server Details

• Server: github
• Changes to: readme.md

Motivation and Context

This will help in setting up the correct github MCP. It wasted my time. This should help others

How Has This Been Tested?

Yes, on my machine

Breaking Changes

No

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Protocol Documentation
• My changes follows MCP security best practices
• I have updated the server's README accordingly
• I have tested this with an LLM client
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have documented all environment variables and configuration options

Additional context