* CHANGE: Add PowerShell Pester v5 Testing Guidelines
- Introduced a new guide for PowerShell Pester testing best practices.
- Covers file naming, test structure, core keywords, setup/teardown, assertions, mocking, and best practices.
- Provides examples and configuration details for effective test execution.
* CHANGE: Remove unnecessary code block from guidelines
- Removed the empty PowerShell code block from the PowerShell Pester v5 testing guidelines.
* CHANGE: Correct file naming pattern in guidelines
- Updated the file naming pattern from '**/*.tests.ps1' to '**/*.Tests.ps1' for consistency with PowerShell Pester v5 conventions.
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Co-authored-by: Matt Soucoup <masoucou@microsoft.com>
