Add admin check to uninstall of machine font (microsoft#5779)

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Fixes microsoft#5774 

Adds an admin check to the font uninstall flow.

Non-elevated uninstall of machine font
<img width="585" height="63" alt="image"
src="https://github.com/user-attachments/assets/e02bea39-8e88-42fc-9355-7b90b875e44a"
/>

Elevated uninstall of machine font
<img width="517" height="53" alt="image"
src="https://github.com/user-attachments/assets/d22d502f-64d2-4f4e-8bed-6a8f8ada9071"
/>


Tested:
* Uninstall of machine installed font succeeds from elevated command
prompt.
* Uninstall of machine font from non-elevated command prompt fails.

No release note update required for this, fixes a bug in unreleased
code.

- [x] I have signed the [Contributor License
Agreement](https://cla.opensource.microsoft.com/microsoft/winget-pkgs).
- [x] I have updated the [Release Notes](../doc/ReleaseNotes.md).
- [x] This pull request is related to an issue.

-----

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Author: dkbennett

src/AppInstallerCLICore/Workflows/FontFlow.cpp

@@ -315,6 +315,12 @@ namespace AppInstaller::CLI::Workflow
                 fontContext.Scope = scope;
             }
 
+            if (fontContext.Scope == Manifest::ScopeEnum::Machine && !Runtime::IsRunningAsAdmin())
+            {
+                context.Reporter.Error() << Resource::String::CommandRequiresAdmin << std::endl;
+                AICLI_TERMINATE_CONTEXT(APPINSTALLER_CLI_ERROR_COMMAND_REQUIRES_ADMIN);
+            }
+
             auto uninstallResult = Fonts::UninstallFontPackage(fontContext);
             if (uninstallResult.Result() != FontResult::Success)
             {