Chore: Deprecate Cake.SimpleVersion - Update documentation to use SimpleVersion.Tool

[Kieranties]

Description

Removes custom implementation of Cake plugin in favour of a dotnet tool. This increases the integration cost slightly for cake, but allows targeting a singular x-plat implementation of the base libraries and tooling for use in any build system.

Change Type

• Documentation: Changes to docs are included
• Infrastructure: Changes to build scripts/non-deliverables
• Bug Fix: Fixes an issue in implementation
• New Feature: Adds new functionality in a non-breaking manner
• Breaking Change: Implements a fix or feature in a breaking manner
• Other - Deprecates the Cake.SimpleVersion package.

Quality

• Unit tests have been added/updated
• Local builds/testing are successful
• Code coverage has not decreased
• Code comments have been provided (where appropriate)
• Core styles have been followed
• Documentation has been added/updated