misc: prefix ValidationTask with I, it's an interface

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src/Ryujinx.BuildValidationTasks/IValidationTask.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.BuildValidationTasks
 {
-    public interface ValidationTask
+    public interface IValidationTask
     {
         public bool Execute(string projectPath, bool isGitRunner);
     }

src/Ryujinx.BuildValidationTasks/LocalesValidationTask.cs

@@ -7,7 +7,7 @@ using System.Text.Encodings.Web;
 
 namespace Ryujinx.BuildValidationTasks
 {
-    public class LocalesValidationTask : ValidationTask
+    public class LocalesValidationTask : IValidationTask
     {
         public LocalesValidationTask() { }