(MAINT) Fix broken links

This change fixes the broken links in two machine configuration articles:

1. The first site-link to moved content has been corrected to use the new
   canonical URL. The redirects have also been fixed for that URL separately.
2. The external link to the Ubuntu man-page has been replaced with a link
   to the manpage for `sudo` hosted by the Sudo project itself. Contextually,
   the article suggested `su` in the original link but used `sudo` in the
   examples.

   The original link was reported as broken because the Ubuntu website uses
   programmatic redirection instead of URL-based redirection. Clicking the
   original link resolved in a browser, but not for the automated system.

Author: michaeltlombardi

articles/governance/machine-configuration/machine-configuration-azure-automation-migration.md

@@ -284,7 +284,7 @@ the configuration to a MOF file and create a machine configuration package.
 Some modules might encounter compatibility issues with machine configuration. The
 most common problems are related to .NET framework vs .NET core. Detailed
 technical information is available on the page,
-[Differences between Windows PowerShell 5.1 and PowerShell (core) 7.x](/powershell/scripting/whats-new/differences-from-windows-powershell)
+[Differences between Windows PowerShell 5.1 and PowerShell (core) 7.x](/powershell/gallery/how-to/working-with-local-psrepositories)
 
 One option to resolve compatibility issues is to run commands in Windows PowerShell
 from within a module that is imported in PowerShell 7, by running `powershell.exe`.

articles/governance/machine-configuration/machine-configuration-create-test.md

@@ -50,7 +50,7 @@ To run PowerShell as "LocalSystem" in Windows, use the SysInternals tool
 [PSExec](/sysinternals/downloads/psexec).
 
 To run PowerShell as "Root" in Linux, use the
-[Su command](https://manpages.ubuntu.com/manpages/man1/su.1.html).
+[sudo command](https://www.sudo.ws/docs/man/sudo.man/).
 
 ## Validate the configuration package meets requirements