ops: update AzureSignTool from 5.0.0 to 6.0.1

Author: jacdavi

utils/workflow/Install-AzureSignTool.ps1

@@ -6,5 +6,5 @@ function Install-AzureSignTool {
 
     Write-Warning "Installing AST..."
 
-    dotnet tool install --global AzureSignTool --version 5.0.0
-}
+    dotnet tool install --global AzureSignTool --version 6.0.1
+}