Update health tests to execute locally per role

[arudell]

Description

Summary of changes:
This pull request includes several updates and improvements to the SDN diagnostics scripts. The changes primarily focus on adding new diagnostic commands, updating configurations, and enhancing existing functions.

New Diagnostic Commands Added:

• Added new commands such as Debug-SdnGateway, Debug-SdnLoadBalancerMux, Debug-SdnNetworkController, and Debug-SdnServer to the src/SdnDiagnostics.psd1 file.
• Added additional test commands like Test-SdnClusterServiceState, Test-SdnDiagnosticsCleanupTaskEnabled, and more to the src/SdnDiagnostics.psd1 file.

Configuration Updates:

• Updated the src/modules/SdnDiag.Health.Config.psd1 file to include new health validation tests such as Test-SdnDiagnosticsCleanupTaskEnabled, Test-SdnNetworkControllerApiNameResolution, and others. [1] [2]
• Added new health fault configurations to the src/modules/SdnDiag.Health.Config.psd1 file.

Function Enhancements:

• Modified the Repair-SdnDiagnosticsScheduledTask function to accept a mandatory TaskName parameter instead of using a switch statement to determine the task name. [1] [2]
• Simplified the Confirm-IsCertSelfSigned function by removing the type constraint on the Certificate parameter.

New Classes and Functions:

• Introduced new classes MuxConfig and MuxStatistics in the src/modules/SdnDiag.LoadBalancerMux.psm1 file to handle MUX configuration and statistics.
• Added new functions Get-SdnMuxConfig and Get-SdnMuxStats to retrieve MUX configuration and statistics.

Change type

• Bug fix (non-breaking change)
• Code style update (formatting, local variables)
• New Feature (non-breaking change that adds new functionality without impacting existing)
• Breaking change (fix or feature that may cause functionality impact)
• Other

Checklist:

• My code follows the style and contribution guidelines of this project.
• I have tested and validated my code changes.