tests: add more test coverage

src/AltGen.Console/Generate/GenerateCommand.cs

@@ -40,7 +40,6 @@ sealed class GenerateCommand(
 
     public override ValidationResult Validate()
     {
-
       var pathExists = _fileSystem.File.Exists(Path);
 
       if (pathExists is false)

src/AltGen.Console/Usings.cs

@@ -1,4 +1,5 @@
 global using System.ComponentModel;
+global using System.Diagnostics.CodeAnalysis;
 global using System.IO.Abstractions;
 global using System.Net.Http.Headers;
 global using System.Text.Json;
@@ -13,4 +14,4 @@ global using Microsoft.Extensions.Hosting;
 global using Microsoft.Extensions.Logging;
 
 global using Spectre.Console;
-global using Spectre.Console.Cli;
+global using Spectre.Console.Cli;