Added GitVersion, AppVeyor, Octopus Deploy, and Cake to Awesome .NET list

[nileshsheth]

Summary

Added the following DevOps and Build Automation tools to the Awesome .NET list:

• GitVersion – A tool for versioning .NET projects using Git history.
• AppVeyor – Continuous Integration (CI) and Deployment tool for .NET applications.
• Octopus Deploy – An automated deployment and release management tool for .NET.
• Cake – A cross-platform build automation tool with a C# DSL.

Why are these useful?

• These tools help streamline build automation, CI/CD, and deployment in .NET projects.
• They are widely used in the .NET ecosystem and provide great flexibility for developers.

This addition will help .NET developers discover powerful DevOps tools to improve their workflows.

[pleb]

@nileshsheth duplicate links.